I previously recommended to wait 'till the platforms announced what projects were leaving, then out of those projects, look at the ones that are on your watchlist to give them priority. Generally you could end up having a diverse array of movies to watch for the month.
I have like 2000+ movies I want to watch on a list. I frequently find myself overwhelmed because of this. I figured out another way to determine what to watch. I put them on one of those sites where you can put a list of things for sweepstakes and just let the site choose. As long as it's on a platform, I'll watch. Just watched Wizards (1977) this way.