Need Advice for incubator

[Icefire]

I'm currently breeding Leopard gecko with a sample heater in
2 inch of water in an styrofoam box.

Since I want both male and female and will probably breed
Bearded dragon and collared lizard next year (with my 30 gecko)
I need better incubator.

I'm planning to make a 30 inchx14inchx14inch melamine incub.
isolated/sealed with 1/2in styrofoam with silicone.

Should I use lights to heat the incubator with a thermostat and place
a ~2-3 litter of water on the bottom to create humidity like this:



or I should use the plain bac of water on the bottom with a water
heater and not use thermostat ? like this:




I'm planning to use a plexyglass AND a styrofoam/melamine door
so I could look at it without dropping the temp.

I'm also planing to glue a circle with Hot Glue in delicup and put the egg directly on it so it won't roll over (no substrate, 100% Relative humidity)

any tips?