Increase the number of slots in constant combinators.
Mods introducing new content into the game.
Entities which interact with the circuit network.
the performance impact of combinators with large number of slots is substantial, you might want to put a warning to limit the number of total combinators on the map (and perhaps even an enforceable limit as an option).
That's good to know! I'll add something to the README.
Now that I have a better handle on modding Factorio, I'm going to try to make a separate combinator that's larger.