It was appalling how much energy she was wasting just hopping around in circles, over and over again. Not really necessary because he didn't put much effort in, or have any technique.
(edit: also surprised at the youtube comments that say she won. The video cuts each time he knocks her down, which is often.)
From a practicality standpoint? Brazilian jujitsu, Marine Corps Martial Arts and its Russian equivalent Systema, or Krav Maga.
In terms of fun? I've always been partial toward Savate, but there's no place to learn it where I am.
But I'm more into archery (it's a martial skill) anyway, instinctive shooting.