I've played around with the Engineering and Developer menus of the Head Unit and found some interesting stuff.
First of all, disappointingly, it seems like (at least mine) doesn't have onboard Wi-Fi, GPS or Cellular. Some other markets seem to have these features in hardware, but just disabled, so they can be enabled by just installing the necessary utilities via abd.
In theory, if your Head Unit does come with onboard Wi-Fi at least, you should be able to enable Wireless Car Play or Android Auto as well as the Android + QNX based platform does support them but it's just disabled. If the unit also has onboard GPS, you can directly install navigation apps as well.
I was able to access the ridiculously detailed audio tuning menu but wasn't really able to make sense of most settings despite being a slight enthusiast. I'm sure a proper audio / sound engineer is going to have a blast. I did disable Auto Volume Leveling though, which was annoying me.
Interestingly, it seems like the car can be configured with 10+ channel audio in some markets. Also, apart from Heated and Ventilated seats, some markets also seem to have the option of Memory profiles as well as front Messaging seats. Obviously, enabling these didn't have any effect in my car since it lacks the actual hardware but I was hoping at least Memory profiles would work.
You can also apparently play with the torque curves for some reason, though I didn't mess with this because of safety concerns.
The main reason I was tinkering with the Head Unit was to see if I can enable Automatic High Beam Assist from some hidden settings, but it seems like that just isn't controlled by the head unit at all and it's supposed to be a physical button on the Headlights stalk that is missing in the units sold here.
I'll try plugging in a USB Wi-Fi dongle later and put the unit into TCP/IP mode and see if I can still sideload apps directly via adb.
