The game slows down sometimes, for no apparent reason. It would be nice if that didn't happen. Apparently related to the off-screen entities, but maybe that shouldn't matter?
Some possible solutions:
Automatically skip the ticking of off-screen entities when the framerate drops
Tick only some of the off-screen entities, e.g. the first half on one frame and the second half on the other frames. The fraction can be scaled according to the framerate.
The game slows down sometimes, for no apparent reason. It would be nice if that didn't happen. Apparently related to the off-screen entities, but maybe that shouldn't matter?
Some possible solutions: