If the camera is on it produces some heat anyway, I suspect as a by-product of operating. It sounds like Durzel had a specific issue, I've had very little issue with misting on mine after pre-conditioning the car. Main issue is low sun (not many solutions for that) and raindrops on the outside of wing and B-pillar.It would most likely fix the condensation issue. I did some tests with very gentle warming of the camera window from the outside and it hardly took anything to clear the glass.
I don't know about compatibility with camera imaging.
Again, even minor retrospective changes that include wiring / power supply changes can be a big headache.
I did consider hydrophobic lens sticker things, but ultimately decided they were likely to be BS.