Dual druids... When one's getting damaged have it heal the other and vice versa+self heals I imagine would be quite a nightmare. Roots, force of nature, can do major DPS as a boomkin and can still pop out and heal-reshapeshift.

Lots of flexibility. Ever got bored with boomkin could run them as feral. Interact with Target is how you melee and works pretty good. They sometimes will just run off for no reason in lag or you spam the IWT button too much.

ShadowmeldX2 can also be fun.