Well, in my opinion, you do not need a big size or muscular female player. He needs a female player who is able to set the ball for him, the one that can match ZYL/MJ/Butet/CP skills, that's the purpose of front court double player. Same thing with MD front court player.
that's why he need to stop doing unnecessary activities such as clubbing, gambling, drinking, smoking etc... coz that burden his stamina and physical form. He may can do those things only when he retired...
It depends on the player himself whether he wants to work his ass hard to accomplish what he has not. If he gets satisfied by his achievements to date, then we can't expect more.
I think he has said before that he doesn't like to play mixed doubles - or at least he does not like to play 2 events at once. The last time he did that in a local tournament he had a back strain on finals day.