Here's a funny thing to consider: People speak a lot in different styles, yet it somehow makes sense to write in only one style.
I'm actually in favor of older literature. In older literature, characters didn't try to be personal what comes to their voice. These days, it's suddenly all the rage to use dialectual, colloquial language - it's probably easy for the reader to then tell apart the laidback and stiff-necked, the peasants and the nobles, the farmers and the townsmen.
But I can't. I'm not a native English speaker, for starters. And even my dialectual and colloquial langiage knowledge of Finnish is somewhat limited. I could invent a whole new dialect for the stories, but that would be kind of tricky too. Yet, if you look at the older books - characters exhibit some wonderful personality even when they, superficially, speak similarly.
So I plan to get this covered what comes to wordiness, complexity and other related things.
Let's compare: Facyr is basically the boring, background-dwelling author-self-insert who just does things and won't get noticed anyway. He's not overly wordy, goes to obvious conclusions, and won't say them unless they're not completely obvious - he won't bother his friends unless they need to know something. Faira is cunning and smart, Gnedrnygr is only smart. The big difference is that Faira speaks more and Gnedrnygr ponders things a bit more before saying them aloud. Gnedrnygr knows a lot - Faira and Facyr don't know as much, but if they can somehow get the wisdom out of Gnedrnygr, Facyr can apply it practically and Faira can formulate something out of it.
And here's one of the problems I noticed in my writings: Most characters tend to be wordy. They babble and babble and babble and use complex language. Mostly because when I write random things, I tend to babble and babble and babble and use complex language. So I have to fight back - basically, if the character isn't a total geek, they shouldn't talk that much.