Doing a quick test of the PWM control, I can see a nice Linear temperature profile. This was just a quick test with giving the oven about 5 minutes to stabilize at each point.

The small blip in the graph at the bottom is probably because the door was more or less open. Only went to 40% but the results are nice and encouraging. I've also made a few updates to the code and one of the things I plan on adding later is a test cycle that tries to see what the thermal profile and curve will be for many temperature variants.

I would also love to add a servo to control the door so it can be opened and closed by the control board for temperature control.