The homebrew version I use has a ton of unique mechanical features that emphasize athletic maneuvers and grappling (tied to the base class progression); it allows tertiary score options such as Charisma for brawlers that have more of an entertainer background. The subclass archetypes are fight clubs (gladiator, improviser, pugilist, wild one, wrestler, and spellfist). The spellfist is particularly cool as it uses a unique casting mechanic involving magical tattoos/body art, but they are all quite distinct from one another in terms of both flavor and crunch.