I would like to mention that dbs handled the frieza stuff a lot better then the movie. They elaborated heavily on frieza's return and growth in many ways,like tagoma being forced to fight frieza over and over to make frieza stronger. It also did a fairly solid job of returning him, as once he was back for the tournament (one day) he showed his sadistic side and stayed remarkably in character, caring only about himself and doing anything to win. frieza was great in dbs, and made dbs okay.
I watched Dragon Ball Super, and I thought it’s version of Res F was worse than the movie. Much worse. If you like it, that’s fine, but my opinion stands: Bringing Frieza back was a bad call.
I agree that the Tournament of Power was good, but I don’t think it would have been any less good if Majin Buu had shown up like he was supposed to. The whole tension of recruiting Frieza was that he’s a total jerk but we’re desperate, but now we have to honor his terms if we make it out of this. Except the tourmanent ended in the final episode, so we never got to see the the characters struggling with the consequences of Frieza being revived again.
The Broly movie picked up on that, sure, but the only one who seemed to take Frieza seriously as a threat was Vegeta, and that didn’t last very long. Hell, they had him dead to rights at the end and let him go. Why? So he can come back in the next movie or Dragon Ball Super 2.0, I guess, except it’s been almost a year and neither of those things has been announced.
Here’s the thing, imagine if Majin Buu had been in the Tournament of Power. He could have fought the whole time in that creepy buffed-up form he had in that one episode, or he could whip out a bunch of new forms and screw with everyone that way. Or Champa could recruit his own universe’s Majin Buu counterpart, and they could interact like Frieza and Frost did. Or they could fall in love, and spent the whole tournament making out under the ring.
There’s a ton of stuff you can do with Majin Buu, and it’s all 100% fresh and new because they never do anything with Majin Buu after he turned good. Just like they never do anything with Tien or Yamcha and the others, because we need that screen time for Fuh-reez-ah-sama to stand around and look smug for the millionth time.