You are the biggest producer in cinema. You run Big-Ass Studios and what you say goes.
Take any movie, good or bad, from any time in history and act like it has never been made before. Do you want to cast the same actor in their respective role, or do you want somebody new. Can a young James Cagney be in the same movie as a middle-aged Gary Oldman? You bet your ass he can.
Who will direct it? Who will score it? Who will be in charge of the photography? Will you call for a re-write or leave it as is? Do you want to change the name of Big-Ass Studios?
The change doesn't even have to be to improve the film. Maybe you'd like to see a serious movie with comedic actors.