I use a “degoogled” ROM with microG. And I use android auto “without” the play store.
By using the following tuto and without root, I’m able to use android auto without having its dependencies installed ( play store, maps, google tts…)
https://community.e.foundation/t/how-to-run-android-auto-without-google-apps/64578.
It’s not an open source alternative to android auto, but it limits greatly the interaction with google. I have comaps and osmand from fdroid that works in the android auto app this way.
If you have google apps on your phone, maybe you can uninstall or deactivate the dependencies for AA, and follow the tuto, there is a chance that it works.
Why not ? There is so much mods that you can play new adventures, with the feeling of being at home.
The base game is full of flaws, but the community makes it really enjoyable.
The balance of skills, the graphics, even the story can be changed. That’s why I like to play it again and again. I can play a Skyrim that people built. And with the perks mod, I can build so much differents characters, I really love that.
And with skyblivion coming this year, I’m not even close to stop playing it.

It’s the combat part of the game that made it hard to me to play Skyrim. I use some mod and play a mage to avoid playing with weapons, because I find the combat system slow and boring.
I’m replaying Dark Messiah. The game aged, but its combat style is still as dynamic as I remembered. Back then, It’s because I compared it to the Oblivion one that I didn’t played Oblivion more than a couple of minutes.
Thank you so much for your work !!! It made things so much easier for me when I started degoogling !!