How many character(s) do you get to select and change the portrait of? Are there voice options or do males and females have a default set of voices for actions? Also, do you have to write a biography of sort for your character(s) like in Wasteland 2?
Well you have your main character, but you can also hire adventurers at inns and you can fully customize them. The companions you meet along the way have fixed portraits and appearances of course, as well as their own personalities voices, backgrounds and agendas. They are entirely optional however so you could have a party made up entirely of characters you created A la icewind dale.
There are voice options for your character. I want to say 4 male and 4 female but it might be 3 each.
I saw a biography page in the character screen. in the backer beta its prefilled based on the background you chose at caracter creation. Dont know how it will work in the full game.