There are quite a few sequels that I'd consider greenlighting.
Dreamfall Chapters, because Dreamfall ended on a massive cliffhanger.
System Shock 3, for the same reason, and because I want a game that plays like System Shock 2, but with modern graphics.
Jedi Academy 2, because the Jedi Knight series had insanely good gameplay, and were the only Star Wars games that actually made you feel like a Jedi.
And finally, Homeworld 3. Homeworld was a spectacular game, but the gameplay, as unique as it was, could've been better. Homeworld 2 improved on the first game in almost every aspect, and the gameplay was at its tightest. But just when Relic had perfected the Homeworld formula, they abandoned the franchise, and went on to make a series of RTS games about fat space marines. Not cool.