I love games like Subnautica and Endless Ocean (own both games on the Wii) and would love to see a game where you work through the career of being an undersea explorer. Starting off looking for simple targets, like small ships lost off the coast of a continent, working your way up to better equipment (side scan sonar, ROVs, etc) and bigger targets (like a few famous shipwrecks). There was an old PC game called Sea Rogue where you searched for shipwrecks and recovered treasure, maybe a remake of that game but with full 3D environments like Subnautica. I saw a undersea explorer game on Xbox's game store but haven't heard much about it though.