I was thinking of other sports with subjective scoring, like figure skating. Maybe there are compulsory dunks, either assigned by the panel or drawn randomly out of a hat in front of of the crowd. Then each guy is graded on these dunks. So all the participants are compared on the same dunks. Then if you make the next round, you can do your routine, so to speak.
Slightly different but they had the dunk wheel many years back. Players spun a wheel to see what type of dunk they'd do. It killed the creative aspect. I see that being an issue with what you describe as well.
I think they should pause the contest for a couple of years and allow the hype to return. Maybe do it every other year or every 3 years so it doesn't seem so watered down.
The more I think of a team type contest the more I'd be interested in that. Every team competes and goes head to head throughout January leading to a final 4 at All-star Weekend. Then it's more of a free for all instead of head to head. If the Suns made it then Collin could go out there with Fleming to throw lobs in round 1 but Oso could throw lobs to Jalen in the finals, for example. Maybe even allow 60 seconds to put on a show and the team is scored as a whole instead of just a dunk. So like a synchronized scrimmage, kind of.