Personally if you haven't already played them, play the Zero Escape series. If you like puzzle games, especially escape rooms, this is a good series.
Zero Escape: The Nonary Games include the first two games of the series.
Zero Time Dilemma is the final game in the series.
God Eater is good too
Do you have a gamestop in your area? that's where i get most of my vita games. Highly recommend Persona 4: Golden. Freedom Wars was pretty neat but I never beat it, and the Call of Duty multiplayer wasn't terrible either, I had some fun when i wasn't near my pc or console. I love my Vita to death though.