I don't have a real problem with mobs and such. I do "love" some quest that states the level you should be at to do it, but really means you should be 3 or 4 levels higher than what it says or you die. And another thing, the idea that 4 level 15 npcs can kill 2 level 20 jedis is crap.
I got this game for the story only, not for the multiplayer (as I hate MMOs). When I heard that Bioware was making this game I thought great, I can finally finish story from the Knights Of The Old Republic series. Instead, I have a game with a good story, a game that I must pay by the month to play (not that big of a deal), and a game that is making me mad more and more. As I sated above, I've been having trouble with quest. I can have a group of 3 or 4 npcs that are 4 levels below my character and they will slaughter me not matter what weapons, armor or what not I have. It doesn't happen all the time but when it does, I die. After the 10 try, I give up and go to another quest. This is one reason I'm beginning to hate this game and the fact that a I can't bring a friend that is a higher level than me in the same phase is crap too. I think this game should have been a SP game (I was hoping it was a SP game when I heard about it), although I do like the idea of a multiplayer story (I would have done things differnet, as would anybody else).
If a developer is reading this, I would love to see a SP mode that still uses the subscription (for your sake), but toned down for a "story only" play through or just make KOTOR III. I would play it least 10, 20 times back to back like I did when KOTOR and KOTOR II came out (thinking of playing them again now since I started to play SWTOR) just to play through with different choices etc... You can also keep the characters from interacting with the multiplayer side of the game.