Well said, an elite Kang or Mileena can destroy pretty much the entire cast of MK2, with a few exceptions. This is an extremely fun match, whether you are Liu or Mileena.
I have to disagree that Kang has the edge though.
btbb99 and I did 20 matches last year of Kang vs Mileena, where we each used Kang for 10, then Mileena for 10. we both whomped each other's Kang 9-1 with Mileena. I've played the best Kangs out there, and when there's no lag, I don't have too much trouble beating Kang with Mileena. Overall I say it's a 6-4 matchup in Mileena's favor, and I think that's being a little generous to Kang. Liu is the best counter in the game to Mileena though. His low fireball takes care of her sai spamming, and his bicycle kick forces her to play more defensive than normal.
I think Kang's best bet is mixing it up, and staying away from Mileena. If he uses high fireballs, it's almost impossible to hit him with Mileena's teleport kick. It's the low fireballs that get him in trouble- Mileena can block them, and then roll within sweep distance, or JK/sai him. Only use low fireballs from a safe distance.
Mileena must stay close, try to apply jab, and be aggressive with crossover kicks, sweeps, etc once she is in close. Limit the air sai, as they aren't as effective in this match as her sais from on the ground are. Throw a few ground sai, goad Kang into low fireballing, then JK/sai him.