I don't know how feasible it is in AGI.. but I played Super Mario RPG a while ago.. and the thing I liked with the battles (which were turn-based) was during each attack, there were certain times you could press a button.. and if you pressed it at the right time, your attack was a bit more effective.
So instead of just sitting there, hitting attack, heal, attack, heal,... you were also trying to hit the button at the exact time too.
- Nick