1) Remember that balancing viewpoints is an art, not a science. For example, not every chapter has to be the same length, nor does every viewpoint character in the book have to have the exact same number of chapters. You’ll only drive yourself nuts if you try to keep to such a precise mathematics. Also, you may make the plot do weird and convoluted things. If the author decrees we must spend six chapters in the boring backwater village which only gets invaded the sixth time we see it, and yet exactly the same amount of time in the center of a daring young heroine’s flight for her life, finding of shelter, building of respect, and gathering of an army, the plot will stutter and stop and start in weird places at weird times. Also, the plotlines that need more room in any sane story will feel abbreviated and cut off, while the author may desperately try to pad scenes she should trim down. No. Bad author. Give the plot the respect it deserves. (See point 2).
You may want to pick a “central character”—not in the sense that he or she is the most important one, but in the sense that he or she rightfully has the most chapters, because he or she is riding a plotline that can make waves and tie in to other characters’ threads. This is a diagram/summary of A Game of Thrones, the first book in Martin’s A Song of Ice and Fire, in which he has eight viewpoint characters. (It does have spoilers, so if you haven’t read the book, I recommend just looking at the list of character names and chapter numbers at the top, rather than scrolling down). The book has 73 chapters, and characters range in the number of the chapters they narrate from five to fifteen. The “central character,” Eddard, gets the 15, because he’s the one running around and doing a good portion of the heavy plot lifting; also, his plotline intersects with almost all the others’ at one point or another, and almost completely overlaps two of characters with the least influence on the story, his daughters Sansa and Arya. There wouldn’t be a point in constantly retelling scenes from Sansa’s and Arya’s POV’s, or in having them narrate events that Eddard has to tell because he’s involved in them and, politically, understands them much better. The story comes out as tightly-structured because Martin spends time shuffling the characters around to see who can narrate best, not following some odd idea of everybody getting equal stage-time.
Not all narrators are created equal.
2) If your characters are the drivers, your plot is the engine. Many, many fantasy series become possessed of Series Rot as their books climb towards the double digits, because the author gets tangled up in developing Minor Character A or Minor Villain B, and launches characters in all directions like ninepins, and loses track of the plot. The plot can barely advance when the author has 15 narrators, and all of them are in different parts of the world, and all of them have to weigh in and report on the events around them—at a glacial pace. And heaven forefend that the author kills one of his narrators, or makes her chapters really short, or has some of them meet up again so that we can get an important event from just one set of eyes. Oh, no, that would work against the grand sweep of the work. Or something.
This is disrespectful to your plot, and that is dangerous. Mistreated plots seem to get fed up with the mistreatment and go away—which would also account for Series Rot.
The larger your cast of viewpoint characters, the more I believe plot will have to guide whom you develop and especially who narrates the story. Just have a triad of narrators? Then you can pick Ms. Necessary and still have room for Ms. Really Cool and Ms. She’s Fun To Write. But when we have twelve viewpoint characters in there, and all of them are there just because the author wants them to be—not because they’re central to the action or can advance a plotline—then we are in trouble.
Perhaps your book is not a locomotive. On the other hand, it should not be a glacier. Look long and hard at your narrators. Think about the reason that they are in this book—the reason that springs from the plot and setting, not the really cool inspiration that let you create them in the first place. Remember, they can still be in the story. But there’s no law that says someone gets to be a narrator because she has a quirky voice. If she’s cluttering up the pages and her story is minor and mostly disconnected from the grand sweep of the story that most epic fantasy authors are so worried about preserving, what the hell are you waiting for? Cut her viewpoint section.
3) Individualize your characters. Yes, that’s obvious advice even in a book that’s first-person from one character’s eyes alone. But with the first-person narrator, you don’t have the additional danger that your readers will turn the page, encounter a new chapter in the character’s voice, and think, “Who was this person again, and why is she in the book, and why do I care that she’s hiding from the guards? I care about Character A, damnit!” And then they flip through the book looking for Character A’s next chapter, and if the book is poorly-constructed enough, they can read along quite happily, because Character A’s story and the story of the viewpoint character hiding from the guards have diddlysquat to do with each other.
I don’t think that you can make your viewpoint characters interesting to absolutely every person out there, as that’s largely a matter of personal taste. (I’ve read reviews where the reviewer talked about skimming a certain character’s chapters, while I thought, “Are you nuts? That was the most interesting person in the book!”) But you can make them individual. You can prevent them from fuzzing into the ether, or making your reader, who has faithfully read the book straight through instead of putting it down for days or weeks, say, “Huh? Who is she again?”
-Don’t give them all similar names. Yes, the advice that applies to families applies also to viewpoint characters.
-Show them reacting to each other’s actions even when they can’t be in the same scene. Perhaps Character A narrates a fight between her and her sister, and the next chapter is the sister’s. She sulks about the fight through an entire day spent apart from Character A, during which she will stumble into the trap that the author wanted her to stumble into. Character A does not cease to exist in her sister’s life just because she’s not narrating the chapter anymore.
-Give them different concerns, goals, stakes in the story. If they all want the same thing, it still shouldn’t be for the same reasons. Reading about three taciturn soldiers and three evil mages who all want to steal the demon’s treasure is boring.
-Stagger them by worldview. The number one fault of many fantasy series I’ve read is to have all the narrators divided into two types: the dark, cynical, jaded ones, and the completely innocent and naïve teenagers who eventually will become dark, cynical, and jaded. Where are the happy people, the oblivious ones, the self-absorbed ones, the aware and determined-to-fight ones, the people who are working to help one sector of society but can’t see the rest? Please to be giving us people who see the world in different ways. Then you get to have the fun of narrators contradicting each other, and giving a non-black-and-white world picture.
-Give them different voices. And no, I don’t mean just dialogue. While authors’ attempts to develop their characters’ dialogue is commendable, it often doesn’t go far enough, or results in oddities like weird metaphors, while their mental voices all sound exactly the same. This ties in with worldview, really. How do your characters think? What do people around them sound like to them and through them? Lord A might seem sulky and snappish in Character A’s viewpoint—not because he really is, but because she doesn’t like him.
4) Who knows what, when, becomes deadly. Keep a close eye on this, especially when you are writing about court intrigue. It can become all too easy to forget that it was Character A and not Character B who discovered that horrible secret, or that Character C will keep marching blindly into the ambush, because it was Character D, several hundred miles away, who found out there was about to be an ambush. And yes, rein in, tightly, your instinctive attempt to shield the characters you love from making mistakes. These are the ideal kinds of mistakes, really—the kind that no one can blame them for, because they’re made from ignorance.
The author’s responsibility is to make sure that the flow of information is as clear as it can be. If Character A would tell Character B the secret, then let her—but mention that they had the conversation, please, or the reader has a perfect right to be blinking in shock when Character B hurtles through the halls with a scream in her throat. If Character D has the time to get a messenger or a carrier pigeon off to Character C before the ambush, that’s fine, but show or mention it; Character C cleverly avoiding the enemy’s clever ambush will seem superhuman otherwise.
And, as always, there come times when you’re going to have to let them take the fall. Sometimes, the very story will work against you if you don’t. Character A doesn’t like Character B, so she has no reason to tell her. Character D doesn’t even realize that Character C exists, so she’s certainly not going to send off a random messenger. Connections between narrators should certainly be present if possible, so that the story doesn’t resemble a series of parallel lines, but they shouldn’t be forced.
5) Condense, drop, summarize, flashback, cut. Most large-cast stories are third-person limited or third-person omniscient. The very great danger with this is that the author will try to describe, tell, or show everything that her viewpoint character experiences. That is another major cause of stalling and mistreating the plot. A book can get long enough just following a single character through every motion he makes. Then add another person like that, and you’ve doubled the problem. By the time it gets to twelve, you’re painting a target on your chest and inviting Series Rot if you try to keep this up. Or, at the very least, you’re inviting books that only cover a few days at a time, instead of the months or years they often need to.
So, learn what can go and needs to. Is a character spending a lot of time in one static place, like prison or a court that doesn’t change? We might need to know she’s been there a week; we don’t need an account of all seven days that basically amounts to, “This stinks. I’m so bored.” Is a character journeying, and doing nothing but journeying, while encountering no one and nothing of any plot significance? Put a little summary of the journey at the beginning of the chapter that deals with the first significant event and move on. Is a character sick, injured, or in a coma? Start with when she wakes up, please. We don’t need to know every single fever dream.
A great way of dealing with this is the “example” passage, or “shown exposition.” Rather than telling us, “Jon and John had been traveling through the wilderness for three days, and Jon still couldn’t trust the smug bastard,” which gets the point across but is boring, try something like, “Jon had been watching John arrange his bedroll closest to the fire every night for three days. He never kept watch, saying they didn’t need to. He shaved with his skinning knife. He snored. He wore a smirk all the time that indicated he had some dire secret, and would not confess it until Jon broke and asked him. Jon would have strangled the bastard if they hadn’t still been seventy miles from civilization.”
This gives us some idea of what’s been going on, without repeating every single time it happens and without simply telling us. Of course, overused, it becomes stale, just like every other writing trick, but for large casts of viewpoint characters where you’ve got to keep on flying, it works well.
6) Be prepared for the emphasis to shift.This is the other side of a coin about choosing a central character and letting him or her have the most viewpoint chapters. That character need not always remain in the center. Your book is going to shift. Be prepared for it to do so.
Perhaps Character A got involved in a battle that you didn’t foresee; you’d planned for him to escape before a city got besieged, but he didn’t. Now he needs to narrate the battle. Meanwhile, Character B, who was central, has gotten trapped in a dungeon. Don’t feel guilty about spending more time on the siege than on the fine art of dungeon dwelling. It’s a sign that you don’t value characters so highly that you freeze them in place and refuse to let them rise or fall.
I seem to keep saying “I will never do this again” when I work with a large cast of viewpoint characters, but I always wind up doing it again.