I would love to develop a ship simulator type game, where you have a research vessel, head out on the open ocean, scan for wrecks (which are scattered around the ocean), make it real scale \ real time, so that you really have to work hard to find one (one 'realistic' mode and one 'arcade' mode with more wrecks and smaller scale, and maybe a 'historical mission' type game where you find a particular wreckage.). Then you can deploy subs \ gear and get up some valuable cargo from the wrecks, ship that stuff back to land, buy better boat \ gear etc. :) That would be something I'd love to play.
And obviously support VR in the game.