I would be happy to plunk down the required capital for Magician Lord 2, Crossed Swords 3, World Heroes 3/4 or just a home release of Neo Bomber Man (or NMB2).
But those are all ADK, & NBM is Hudson, so as for an SNK game, I would be happiest to see a true, storyline-intensive Art of Fighting 4, or just any kind of game that has appearances by all sorts of SNK characters, like Kim (Kizuna Encounter), Geese Howard, the Sakazaki family, the Sports Hero team, etc. A good sequel to Samurai 1 would be worth it as well, as would King of the Monsters, with a new Battle Royal mode!