I use the Enhanced Theme for myself. I have some clients that are only interested in controlling their email, so I have installed the cliomail theme for them.
I've also played around with the Marina theme.
It is nice... tons of bling, but then I went back to the Enhanced Theme since that is what I'm used to.
I think the default theme is enhanced. I use enhanced theme, and I am trying to translate it to Turkish and German, since I have a couple customers, whose native languages are Turkish and German.
I couldn't really find any good themes for DirectAdmins, or I should say better themes than enchanced theme. If you come across a good template for a reseller account, I would be happy if you would share it here.