Lots of after market mirrors support this, but admittedly I've only put them in cars that didn't have a camera to begin with.
I prefer the center console. The rearview mirror is shaped and sized to display the small sliver that you can see out of the rear window which are tiny these days due to increased pillar width, and rounded back to improved crash safety and aerodynamics. The size and aspect ratio of the center console makes it much easier to see details, and doesn't have to compete with bright back-lighting from the sun. Increasing the size of the rearview mirror would be an option - don't know how big you can get before it starts impeding forward view (again, because the front roof slopes down more for aerodynamics than they did in the past).
https://www.amazon.com/Vehicle-Backup-Cameras/b?ie=UTF8&node...
The backup camera genuinely is a great feature, but the touchscreen is itself awful. I agree with Mazda on this (and the US Navy, which is also replacing touchscreens with knobs).
I'm hoping we start seeing a renaissance of car customization -- for example I know that kit cars, almost all of which are pretty dumb - are gaining in popularity. One of the nice things about electric vehicles is the greatly simplified powertrain is going to create a lot of opportunities for customization and DIY, and I hope our regulatory environment is reformed to support that more. In the czech republic, everyone works on their own car and we have a friend who built his own car from scratch, but in the U.S. we see a lot less of that type of autonomy.
1. I know modern engines claim not to need to be warmed up, but I think that's a load of crap. Oil and other lubricants at very cold temperatures need to warm up and there's no evidence that it hurts anything. And it only uses a little sip of gas.