I use/love the theme BlueiPad V2. It's a paid theme ($2 USD) in Cydia. It's just very clean. I particularly like the frames around the icons.
As far as I can tell, all aspects of the iPad get themed in this one. I use Winterboard to have my own wallpaper, mainly because I change it almost daily. But, the rest of the theme is great. Can't recommend it enough.
Marilyn