I disagree. I'm level 33, medicine spec operative and I'm having no issues questing. In fact I'm burning mobs down pretty damn quick and with Vector as my companion there hasn't been a quest we can't do.
Energy is only an issue if you don't manage it properly, and it can be managed pretty easy with TA, Shiv, Surgical prob, etc.
I just learned shield probe, which I'll use after stealth opening on an NPC, then get my kolto probes up, then stim boost, then evasion if need be. All while still keeping energy levels high enough to work on damage but by this time most mobs are dead.
Not to mention our cc abilities like sleep dart and slice droid.
Here's a couple screen shots to show what my character is capable of. I fought these two a few times and it was pretty easy. The second screen shot shows my health right after the last Jedi died so as you can see, no issue with management, DPS or health.
But I guess it all depends on how you play.
Before the battle: http://i.imgur.com/8iU37.jpg
After: http://i.imgur.com/Qtds2.jpg