here is mine
not as technical as you have described but more advanced than your average DIY bator. you might get some ideas from this for your build.
the old saying goes...Ifin it aint broke don't fix it ........ well I say............Ifin it aint broke....TWEEK IT!!
1 = digital scale
2 = P.I.D. temp. controller (holds 99.5deg F rock steady!!)
3 = uninterruptable power supply
4 = 135 amp hour sealed AGM 12v battery for above (provides 2.5 days of power!!)
5 = ¾ plastic laminated plywood box 24w X 14d X 24 t
6 = Omega brand laboratory grade digital thermometer w/ 2 probes
7 = calibrated digital hygrometer
8 = 6ea Rouen & 6ea Welsh Harlequin duck eggs
9 = ½ insulation
10 = 90deg. rotary actuator for auto turning eggs every 3 hours
11 = 4ea 60 watt of ceramic heating elements w/ 2 fans enclosed inside a duct
Temp controller temp sensor is inside a blown out egg filled with KY jelly
One thermometer probe is done the same way. The other is exposed to the air.
Plastic pan on the bottom of the heat duct for humidity.
All components other than the plywood, battery and glass window were purchased off e-bay for less than 150 bucks.
Eggs seem to be progressing fine when candled a few days ago......2 weeks till lockdown.