Devourer DH feels weak?

Not sure if others agree but I've just been levelling my DH Devourer (77-80, I already had a DH I needed to get to max on) and unlike other classes it just dies so easily and seems to take ages to do any damage?

The assisted highlight is basically just Consume and Reap, then Void Ray.

Am I missing something or are they really this weak at the moment?