Excellent stuff GC. Sorry about the communication pause "issues happened".
Let's forget the heater switch idea. I am fine with adding my own switch and have a couple of positions on the dash for it.
Re video switching: I am with you with the crosstalk possibility. Also I once managed to get a monochrome pic after I tried similar where I pulled the power connection and reconnected it.
Re simplified wiring: I am all for that. I gather too that neither camera will be permanently on and running hot which shortens life. People following this thread should keep that caveat in mind.
Some time ago I read that a diode across the relay coil is a good idea to prolong its life. Do you have that in mind too or will it cause other problems?
I showed "The Dreaded" the 'Stang photos and out came the bucket of water
