I have to make a hard choice.
Okay, it's not exactly earth-shattering, but...
Yahoo Avatars adds new stuff all the time so you can dress up your person, add butterfly wings or halos or alien life forms, and change the background. There's a new background that would be so much fun to add here: a Treehouse in the Woods.
But if I do that, I'm never going to have My Own Back Yard again, since Yahoo took out the custom-photo button and there's no way to save it.
UPDATE: We figured it out! Ponytails reminded me that you can save whole avatars in your favourites, so we didn't lose the backyard.
And I do like the treehouse.