I think it would a great idea to increase the pixel size on avatars to 100x100.
Being a veteran of many different messageboards over the years, I can say without a doubt that doing something like this is definitely worth the extra space it takes up, which is minimal anyways, since we are talking about an extra 1-2kb's per avatar.
There seems to be a lot of extra empty space in our name field area on the left handside, so clutter wouldnt come into play either....
What say you?