All right, I thought about it and if I were to be given the reigns to a Wrestling Promotion on HBO I would just go full scripted and make the show about an upper level indy promotion (think ROH) after they get purchased by a TV production company and are getting a television deal. The format would be single camera/fake documentary, dark comedy.
I would want a mix of good character actors and actual pro wrestlers with some acting chops, no wrestlers would be keeping their full gimmicks + names and would instead play a "real life persona" and a "wrestling character". My immediate thoughts for wrestlers would be Joey Ryan (sleezy wrestling character but born again Christian behind the scenes), Necro Butcher (ultraviolent wrestler, with an implied drug addiction that causes him to have sever mood swings in the back), Chuck Taylor (gay villain wrestling character, ostensibly straight behind the scenes but probably actually gay and has severe internalized homophobia/self hatred), Kenny King + Mr. Touchdown (tag team of ultra-athletic dudes who live the gimmick and act like playboys). I also want to have Ultramantis Black in a semi-recurring role as basically... Ultramantis Black who never breaks character (in the locker room, at Denny's, etc.)
The show's protagonist would be the wrestling company's former top star who has just had his "spot" usurped by a body builder type who was hired by television production company who bought the company to be the Champion and face of the promotion's new direction. I was thinking Matt Morgan for the bodybuilder champion, hadn't decided on the protagonist but it would likely be an actor as I can't think of a wrestler I'd put in a leading role right now.
Further acting roles would be writers, agents, and meddling television executives. Another prominent role would be an ex-wrestler with a bad coke addiction who started the company and after selling out to the TV producers is still left as head booker/talent agent. I was thinking Woody Harrelson for this part.
The show would occasionally feature matches, but I'd invoke a lot of wrestling tropes and there would of course be an episode (season finale?) featuring some kind of screwjob/someone going into business for themself.