Also got to agree with the OP here on some aspects.
I have a 34 Sith Marauder who is currently struggling to quest on Taris, I can destroy Elites but have to medpac on Strong targets, and even have close calls on grps of regular mobs. My gear is up to date as much as I can get and I feel I have a pretty good understanding of the class, but still struggle. He's hit walls like this several times before but generally manages to soldier through. Good thing I'm an altaholic and dont mind rerolling untill I'm keen to try him again lol.