About half way through the 4 hours id pause the script and cut the gems, clean the herbs and shit for like 10 minutes then start it again, i wouldn't break per se, i don't see it as an unnatural play pattern to be on for 4 hours of an evening without a break, worked so far.
Great script, got 99 fming with it in about 2 weeks doing roughly 4 hours a day and never encountered a single issue with it, would run forever if you left it.
Only thing i would say is maybe add that it needs to be run in full screen mode, other than that, flawless.