The blaster secondaries are probably the widest variety of secondaries in the game. Energy is a completely different beast than say Atomic or Martial. You need to do the tiniest bit of research and skill review beforehand to see what might fit your playstyle. If you're looking to be more support based, energy and atomic are really good. If you just wanna be an even bigger damage dealer, sets like fire are real good. Martial doesn't really surpass any set, but it's really fun, and that's enough for me.
tl;dr They're fine, just weird.
Edit: I forgot to mention powers like Power Boost can boost my blaster S/L defense into the near 60% territory so there's definitely more to it than meets the eye.