Hi mate, I had similar problem with my small cabinet setup. I bought a new humidifier which was a little too powerful, even on low. Like you said, I was working harder than i should be to control the RH. Temps aren't really a problem with the LED light. I invested in an Inkbird humidity controller and bluetooth sensor. The sensor is like the SensorPush device but less than half the price. My humidifier is plugged into one of the outlets of the controller and I set the target RH and tolerance. At the moment I've set it at 47% with +/- 2%. It made a huge difference. Keeps the RH steady. Definitely worth a look. Hope this helps and good luck with your grow