If you want some recommendations, I'd say if you enjoyed P4G and P4DAN I highly recommend the P3P and both Persona 2 (EP, IS) PSP-Ports. If you also enjoyed Disgaea 3, I highly recommend getting "Disgaea 4: A Promise Revisited", "Disgaea Infinite", "Disgaea: Afternoon of Darkness".
If Steins Gate is your thing, get the Zero Escape-Series (999, Virtue's Last Reward: Complete Collection, Zero Time Dilemma). All of those Games get on sales, so keep your eyes open for it
. The Operation Abyss New Tokyo Series, Danganronpa Series (My fav: Another Episode: Ultra Despair Girls) might also sound like something that could be of interest to you.