I guess a plus for Gabriel is that he doesn't seem to ask for permission to goon (unlike Haley).
And in that Reaves - Gabriel fight clip, Gabriel was basically TKO'd, but roared like he won (possibly because he had a couple solid lefts at the end). That kind of stubbornness and unpredictability could boost his teammates and also act as a deterrent of sorts ("he probably can't beat Reaves, but he's crazy enough to think he can, which makes him dangerous").
