When I do mass upgrades, I open up the Galaxy menu and just spam click on the category I want, waiting until a star I don’t want to upgrade shows up and then skipping it and continuing.
Here’s an image of what I kind of mean.
Basically when you “Lock” a star, you prevent the ability from purchasing any upgrades on those stars, anytime you click on the upgrade on those stars it does nothing and a small message pops up or something.
A filter at the top as well to help with this would be to toggle being able to see and not see locked stars, so you can mass click again.
This would be amazing! I spend a lot of time trying to avoid certain stars and in the larger games, I give up, choosing my time over appropriate allocation of funds.
I would love this feature to both ensure greater competition and give me back some time in my day (for more games of course).