Wait, do I want to pick these members to TEST the game or MAKE IT? Because with all due respect to everyone here, there's little chance of "making a successful game" (as the thread title says) with 10 members of TYM. People here are mostly good at playing games, not making them.
Anyway, if it's testing I'd go with Slips, Dizzy, 16 Bit, REO, Brady, J360, Tony-T, ECT McFly, Mayo and Chef. Though nobody would ever get anything done because Chef and 16 Bit are arguing over something...probably Catwoman.