Hey,
so.. I really, really liked the portraits in BG2, but only very important characters had them. Then I started installing mods for the game (some of you might've read my outdated guide), and I was blown away by the atmospheric difference triggered by a Portrait mod. And those portraits weren't even good - they rarely matched the characters because they weren't custom-made, but grabbed from random portrait sites and resized to fit the game.
But if it were done professionally, with input from the writers and designers - the original creators - and with a uniform style, I think a brilliant thing could be achieved and immersion would profit greatly.
How 'bout it?