I just got rid of the Cat Avatar Generator plugin, not because it's a bad plugin, but because my subscribers have lousy imaginations. To keep this simple, your user names are rather rote. Just not enough to hook an avatar on. It's like that tribe in Africa where the women's hair styles have to be unique. My subscribers, your user names are just not unique enough. So no more avatars.
So how about using a nickname your friends use instead of something you think makes you look special?