For me it got better at level 20! I'm not joking. I love this class so much, I've tried every clas so far except marauder/sentinel, and this class by far is the most action packed class I've played. I never get bored with it at all. The rotations are complex, and dynamic depending on situation, and that keeps things VERY interesting.
I just recently respec'd from Immortal to Vengeance at level 37 for leveling and it was really fun learning a new rotation, and now that I've got it down, i'm having a BLAST! If I use Quinn, the game turns into easy mode because it's nearly impossible to die. And if I want to have a bit of a challenge I'll use Jaesa or Vette.
This class can be challenging to play, but once you master it, it becomes almost GOD-LIKE. Just stick with it man, eventually you'll get it down.