Somewhat flippant musings on theme ideas.
Mutate! - Making a platformer or schmup-like deal with mutating power-ups is tempting from the standpoint of just focusing on a good polished and fun implementation. This could sacrifice the innovation factor, without some cool twists. If this is picked I may take a chance on arena combat between mutating phenotypes of genetic algorithms, though!Mr. Fixit - Spay or Neuter ALL OF GOD'S CREATURES!
Negotiator - Shadow of the Diplomancer (Kissinger Edition): Geopolitical Intrigue, Eldritch Magick
Mysterious Stranger - It may be a challenge to make a game of it, but making composite sketches from procedurally generated witness testimony to find a criminal could be cool.
More Criticals - A fighter where the only hits that count are criticals, and you don't get many of them. Kind of like real sword fighting.