I'd say that its bad movepool is also a big factor: relying on restalk is a killer with this gen's sleep rules, and even it's in it can't really do too much other than hoping to burn something with scald or do some damage with air slash (or toxic I suppose) - it's really crying out for some of its cousin's (skarm that is) moves, i.e. spikes and roost.
then again an offensive rain dance set is also viable, but that is more hindered by its weak Special Attack and the presence of competitors. It's still a very good set though, give it a shot
oh and I like this idea of potf nica