Ideally you do not want it too cold at night or day.. I've had super hot days in the summer where I have to set my mini split to 62 °F so it will run on 3 tons vs 2 (issue has since been fixed) but my plants did not look happy when the temps were going down as low as 58 °F at night when I'd forget to turn it back to 75.
A good example would be 65 °F night 75 °F day. I'm using HPS so my lights heat my plants 2-3 °F hotter than the air temperature, with LED I would likely be running 80 °F day 70 °F night.
My dehumidifiers work regardless of the air temperature due to quality humidistats.