I finished this game last night, and I’m not entirely sure why I bothered to – I think I have a problem, because quite possibly the only reason I finished it was to get more trophies. 
When you first start playing it, it seems fun. The “Darth Vader” prologue is awesome, messin’ up wookies on their home planet like you just don’t give a hoot. But because Vader’s so over-powered and the level is so easy, the few little annoyances are hidden from view until the next few levels.
The target system straight up sucks. For the most part, when you’re “force throwing” an inanimate object (only some of which can be picked up and chucked around) you don’t really have to aim, the game take’s it’s guess at what you want to throw the object at and you pretty well hit consistently.
However when using your other force powers, such as lightning, aiming requires your character to be physically facing the item. The camera direction is irrelevant, so basically you have to walk in the direction you need to be facing… if you’re like me (a chicken, hiding behind cover from AT-STs) it often means your dumbass winds up walking out from behind said cover trying to aim right.
If you don’t get the little square reticules on the object first, your lightning will just go off into the atmosphere. During the “Imperial Raxus Prime” level, right after you used the big fat burners to shoot holes in the shipyard, you have to shoot down TIE fighters with your lightning – a frustrating experience if ever there was one. You see they can fly right through your lightning unaffected, unless you aimed it at them before you started.
I thought there was a giant plot hole, but it turns out it’s explained away in the story’s only canon ending… yeah, if you want to be evil and play the “Dark Side” ending, you get a movie that doesn’t mesh at all with the original three movies (the second trilogy).
My other gripes? With the exception of the Emperor, the boss fights seem to almost get easier as you progress. The level’s puzzles and problems are extremely formulaic, and things like force-blasting through a doorway is an inexact science at best.
I guess if you’re like my cousin, who was a complete and utter Star Wars fanatic, “The Force Unleashed” is probably rewarding. If not, I guess you could have some fun with it.