Since I am only using the cabinet incubator as an incubator, I sealed off all but the two front compartments of the water tray. This allows me to maintain the humidity around 35% during incubation during the early part of the year. Later when the swamp cooler is running, I do a completely dry hatch without adding any water during incubation.
Years ago I installed a Spyder Robotics PID controller in my GQF 1202 incubator. I set the temperature digitally and it controls the temperature within +/- 0.1°F as long as the room temperature stays within +/-20°F of 80°F. It is a bit pricey but has been well worth it to me to have a stable temperature in the incubator without having to worry about the room temperature fluctuating.