If you have played the premises, then you should play Defiance, and if you haven't played the premises, play them >_
First, the graphic is definitely better, and we can describe it as"excellent",and it does not require a very good computer to show its beauty, when I play the game, I use a FX5600, the game is smooth with all effects on.
Then there is the music, not much new track, many are remix version of the old and classic tracks, I like that, but that is just my opinion.
And don't forget the story, Soul Reaver 2 is one of my favorite game, as it has a very good story and full of puzzles which can be solved with your mind ,not with a boring walkthrough.
Honestly, the puzzles are not as good as SR2, but still you don't need a walktrough, enjoy the story, solve the puzzle, and fight some enemies...did I said that the battle system is better then its premise? The battle system has some similarity with Devil may cry, not as good of course,but acceptable.
I did not experience the so called camera perspective problem, and I never lost my way without a mini map or pointer or something like that.People are not like play the game themselves these days, they want walktrough, they want deep analysis, they want auto path finder, what has happened to the spirit of exploring?
Anyway, if you played the premises, you have no reason to ignore this game, and if you haven't played the premises yet, I strongly recommend you to play, at least the Soul Reaver 1 and Soul Reaver 2, It might become one of your favorite game as well.