Disgaea 3 on the Vita is very good. I stopped playing since I got a bit overwhelmed by everything you could do that game....
As long as you aren't trying to do the very very end game content you can ignore a number of mechanics in the game and get by just fine... aka just because they are there you don't have to use them
I didn't bother figuring out how to use innocents properly for the longest time lol.