In RBY and GSC CC, Pokemon doesn't have max EVs but they can normally have all EVs in all stats. In Stadium 2 CC, they have all EVs for exemple. For the all generations, movesets should be most intelligents and most logicals I think.
Pokemon Online's Challenge Cup has always been very stupid to begin with. But I still agree that this could be implemented easily. There is just a limit on how much we want to push intelligence into team building.