> Android Auto sucks.

No, it doesn't. It's a very simple streaming protocol.

It's literally a gRPC-encapsulated stream of h264 frames over a USB connection. With touch events and some car-related telemetry streamed back. You can implement it in a weekend: https://github.com/mrmees/open-android-auto

You can create whatever you want, including just streaming videos onto the head unit or making it play Doom while driving (with steering wheel for input).