I'm not really sure how that'd work out, since I'll also be DMing and controlling Caiden. But if you want to make a duo, you can; my rule is just that they don't spend too much time interacting exclusively with each other.
Yo, Wolfy. Wanna make a duo? I think I'm gonna make a gruff half-dwarf dude so if I post him will you make a character to match, then I can edit accordingly?
As for everyone else, I'll get back to you when I can.