I've not long owned this game, but I can tell you that although the battle and level up system looked confusing at first, they weren't too hard to get the hang of. There's plenty of tutorials on how to understand the battle system, and like Andromeda said, it plays a lot like X-2 with a few elements of XII thrown in.

I wish I could be more help, but yeah I'm only about 10 or so hours into the game.