MMA also lacks much in the way of performance art and acrobatics. Those Wushu guys run circles around us in that area. XMA as well, but I don't find that form as enjoyable, the facial contortions and screaming put me off. But thats just a matter of taste, I mean some people like Jar Jar Biggs, doesn't mean I have too.
My view is that anyone that thinks there system has everything, probably has a pretty shallow view of everything, or is training in a pretty shallow system and hasn't really experienced anything in depth yet.
