Also be sure to disable collisions on any static, non interactable, sprites so you can reduce calculations.
That is actually something I wondered before... does this actually matter? Say I have 1000 background sprites, but I never test any collisions with them in the eventsheet, do they still impact performance? I briefly tested it and it seems to make no tangible difference if it's on or off. And the collision checks/second in the debugger do not change.