I don't think Killer7 should get a sequel. It was a good game, but more importantly, it was one of a kind.
Super Mario RPG 2.
Nintendo, it is time to reunite Mario, Luigi, Peach, and Bowser with Geno and Mallow. Include more of the classic Mushroom enemies and environments while your at it along with a bundle of power-ups Mario has gained over the years.
Perhaps developer AlphaDream should handle the project given its experience with the Mario & Luigi RPG series. It can produce great looking graphics, simple but satisfying gameplay, and amusing dialogue. I mean, Square Enix can't exactly be trusted these days.
Starfox 64 sequel
A reboot is necessary when a franchise has lost part of its soul.
Arwing, submarine and landmaster combat is where it's at! Keep the focus on character interaction through entertaining dialogue and less on storytelling. We want to take on team StarWolf and turn Andross's arrogant lackeys into space dust. Oh and get rid of Krystal!
Can you imagine how good this game would look in HD on the Wii's successor ?