I was thinking this over the last few days wondering what Retro Studios will work on after Donkey Kong: Tropical Freeze. I know many people want Metroid Prime 4 and I do too but how about Retro works on a new Starfox game. A series I think could do with a reboot because the storyline for that game license is getting out of hand due to it being passed around without a consistant developer. If Nintendo would ever would consider doing a reboot. Other franchises Retro could tackle is a Kid Icarus game in the style of an action game (Devil May Cry or Bayonetta style).
So should Retro return to Metroid or move on to something new altogether, what do you think?