At least in WotR, they let me upload my own portraits. That was fun. But Kingmaker... Ugh. That, for me, was the worst part. I can't stand avatars that don't match their portraits.
Uh, you can upload your portrait in Kingmaker as well.
You can? I looked all over, especially after I played Wrath. Huh. Guess I'll look again.
Still. In terms of avatars, you are EXTREMELY limited in Pathfinder. It was so hard to even match my avatars to the portraits I chose.