Yes, he is.
I'd take KK. He took down the Fatal Five solo. He's faster than all three of them and has his ability to see weak points in objects/people. Plus his abilities with his flight ring. Also, KK does have a "super karate" mode where he taps his chi and amps all his attributes through focus of will and energy.
I'd take Val 7/10. The 3 losses being if he gets tagged by Logan or T'Challa with their claws (though KK has a very high tolerance for pain and damage soak).