Icons are good. I think you should do more services, if you want them to be more useful. With the shape this rare, if I would need some other service icon, I couldn't easily insert the icon from other set or make my own.
I guess I'm not real sure what all the benefits of DA are yet. I assumed that if people were interested in icons they would just go through the Deviantart menu system. Are their menus used less than the groups are?