Wow...BG2 is such a great game but I just can't stand the voices and there are few options for the portraits.
I'd like to know if it's possible to transfer voices and portraits from IWD (much cooler, in my opinion) to BG2. It would have been way better if my fighter had that line "looks like I'll have to go on a killing spree...I'm a busy man, I gotta places to go!...step right up, I've got a death plan for everybody"...
IWD has also cool portraits for thieves, a thing I missed in BG2.

look in the read me file of BG2 and it will tell you how to customize sounds and pics.

If I remember correctly, the portrait size and sound files are different in Icewind Dale than in Baldur's Gate II. At the following site, I found some of the Icewind Dale portraits and soundsets that were modified for Baldur's Gate II.

http://havak.db-forge.com/extra.php