I love fast-paced team sports, and I love fighting sports, but mixing them to such an extent might not work
Fighting in hockey is great because in an average game you might see one or two scraps, which are brief, exciting, and serve to punctuate the game.
Sometimes box lacrosse takes it too far. I've been to some NLL games where a fight breaks out seemingly every 5 minutes and it gets to the point where you actually want them to play the damned game.
I hope this "fight football" succeeds, but I'm picturing a demise similar to the XFL.