The one thing to consider, you might not be doing the right muscle movements in your dream so all you may to is create bad practices.

Things i've heard people were successful with are things the are absolute such as playing an instrument (you either get the note or you don't, best with the piano). They don't develop the co-responding muscle reflexes but they DO strengthen the "okay, this finger goes to this key" on reflex which is the part that most people have the most trouble with.