I'm looking for answers to this question in more of a "in your opinion" way than not actually knowing how to do it, so I hope this is the most appropriate place to ask.
So, I've been working on a project for a while now and I have two modes (single and multiplayer). When I made the single player a long while back, I made a TON of global variables for "global" things, like checking if the game is paused, checking if sound is on/off, etc. Later, working on the multiplayer, I realized how excessive my globals were getting and made an invisible "multiplayerVariables" sprite that tracked a bunch of stuff, but of course, that also feels a little excessive.
I've been doing a lot of reorganization on this project recently and so I was hoping to hear what others tend to do to keep track of "common" variables in bigger projects like this.