I personally really like StartAllBack. I just want a clean classic Windows experience.

Honestly, I feel like they’ve made side loading easier and easier as times go on. Used to be that you’d just get a pop up that installs weren’t authorized for that app, then you had to dig through the settings to enable it. Nowadays the pop up has a shortcut to the correct settings page and even visually flashes the right toggle for you to make it easier to find.

It’s not a 100% solution, but many head units will have hdmi input, but you might have to accidentally install the head unit in a way that bypasses the parking brake interlock for it to work while driving. Most phones can utilize a USB-C to hdmi adapter for screen mirroring, although touch data won’t be sent to the phone.