OH MY CHARMANDER now that idea is stuck in my head. They should most definitely call it Pokemon meh, and see what the public thinks. Because that really is all it will amount to, I honestly can't think of many places they can go from here.
All things considered, Grey really would make the most sense. Although 'Colourless'(or something along those lines; 'colourless' itself is too long) could also work.