Awww dude! FFT is fun cause of the updated content and new characters. (God Damn you Aries!) I loved crisis core. Flows really well, controls are awesome, but you will beat it a lil fast

. If you liked Castlevania Symphony of the Night it can be unlocked in Castlevania Dracula X chronicles. Worms open warfare 2 is mind numbing fun. I dont know about the puzzle games. Brave Story is a good classic rpg with 3d environments and turn based battle.
Last but not least you can just hack da bitch and put what you want on it. Not sure if psp roms work but you can load it with ps1 goodness.