Well if Uncharted and Assassin's Creed were able to be done, then Tomb Raider would fall in nicely with those.
With Resident Evil and Socom mentioned above, I think a game that reminded me of Socom gameplay in the Resident Evil world might make a little sence, since it was made by Slant Six, makers of Socom: Fireteam Bravo 3 on PSP. I haven't played Fireteam Bravo 3, but have seen people post that they liked it.
Anyway, Resident Evil: Raccoon City had a similar feel to Socom on PS2 to me, and supports 4 player coop, and has 4 vs. 4 multiplayer. I know alot of RE fans didn't like it, but I've thought it might be a good fit on the Vita. Just a thought, since this thread seems to be about thoughts.