I was always hoping for an up-ressed collection of the Black Panther games, but they're lost to the obscurity of time too I guess.
In fact, there was very little PSP -> Vita porting, especially odd considering there seems to be a small but noticeable amount of DS -> 3DS porting (most notably from Atlus recently).
A Black Panther collection on Vita is guaranteed to have sold more than the Wii U port of 1 & 2. Then again, a Vita port of 1 & 2 still would've sold more than the Wii U one.
Atlus Japan doesn't really have much of a PSP catalog to mine. It's mostly just Dept. Heaven games no one cares about or ports of older Atlus games.