Oathkeeper Wrote: How about doing what google does to default avatars? Take the first letter of their username and with a colour(or the default one) make the avatar.
This would probably look good for the first two months simply because it's a change but I don't think this would improve the appearance of new users long-term. One thing I thought about is adding thousands of avatars to the site and you pick one out of a few randomly selected when you register with a notice that you can change the avatar later on.