As a snail player - see mountbaras game guide, I quite often produce movies up to the completion level needed to earn sp or others rewards. Similarly, if there is a DS-task for customized movie covers, I stop a movie at the 2-star level, since movies give quite a bit of xp that you want to avoid playing for ratio (i.e. more skill points per level gained).
Since movies can last up to three hours shooting, often times I loose track of what the rewards for each completion level were when I started them and wonder whether I should finish them and to what level. Also, fans can be gained at lower completion level, which I think is pretty much undocumented and under the radar for some players.
Therefore, itd help this playstyle to show the rewards for each star-level during the production of a movie. All playstyles would profit from knowing whats to be gained to get to 2-star or 3-star completion, since forgetting a movie begs the question: do you want to extend it or not - difficult decision, if you dont know what you gain from it!
Hovering over each star-level, the UI could help out by showing the fans and other rewards gained at that level.
Check this mock-up for reference: