I think PokeStar Studios showed promise, but the format wasn't interesting enough to justify the limited amount of choices you had in the huge amount of scripts. Pokeathlon still seems to have been the best of the mini-games, but a merger of Contests and PokeStar Studios would be promising, imo. "Use a cute move here, but you also need to OHKO with that move!" etc. Show a list of what's required and expected for each movie in-game before signing up for that movie, and don't force you to go through it with a rental first each time.
actually the most interesting aspect of it is to figure out the exact sequence of moves/options that you need to execute in order to obtain the best ending
the rentals were specifically designed for the movie, so not forcing the rental in your face the first time makes it even more awkward than it should be
of course, what could've been better done was to take out the randomness factor (i've had shoots that were completely ruined because of an untimely crit or a random scald burn that shouldn't have been necessary)
For me, the movie I had the worst luck with was with Sabrina's and the doors, due to how I would have bad luck trying to perform them correctly.
Otherwise, I liked how the movies were sort of like puzzles to try and solve, and getting Strange Endings and making my Pokémon into stars was just cheesy enough for me to sink time into. It also helps that it's one of the more fun Trainer Card achievements in the series, AND you also get a lot of cash for doing well in movies. It's a real win to you, as the player.
I personally thought that the PokeStars Studios not only as a welcome break from the typical hum-drum of Pokémon games, but also explores more the Pokémon world itself through its cinema and actors (ex: Sabrina, Brycen)