If you liked Paper Mario, give Super Mario RPG for SNES a try. The battle system is somewhat similar. You won't be disappointed.
I second this recommendation. Super Mario RPG is a great game.
I liked Crisis Core, but the plot had more holes than Zack after a while...
[spoilers]It was like every character was too busy trying to be dramatic in their own little way to make any kind of fucking sense. Zack's lines often were just blind generic determination. Genesis was so busy trying to be poetic that he didn't realize he was in the middle of a conversation... much less a coherant plot. Angeal just did shit at random and when questioned about it, felt that dramatic silence was an answer. He literally covered himself in clone monsters to become a gigantic clone monster for absolutely no reason at all. There was no motivation pushing him to do half the shit he did. The only honestly good characters were the ones who already had personalities established by the original game. Cloud was a loveable underdog pussy who had a crappy job, Aerith was still that girl next door type who was legitimately interesting, Sephiroth was delightfully intimidating as a villain and a hero turned rogue.[/spoilers]
and if you like paper mario super mario rpg, you will LOVE the mario and luigi rpg series.