You can take a look here: https://fosstorrents.com/
You can take a look here: https://fosstorrents.com/
Most people I know just use Arch Linux and the AUR. It seems to be the easiest system around for maximal package support and it's well maintained.
On the contrary AUR seems to have a lot more binary packages than source packages in my experience. Tons of package also have a "-bin" version (e.g. yay).
Your "unsupported" comment is a bit weird. It's the AUR user community that supports Arch and makes AUR compatible with it. I don't know why somebody would contemplate the other way around. I mean, it's the while philosophy of the AUR.
I've been using it for the past 12 years and I rarely got any issues with it. I think you fear mongering quite a bit. Sure, you get over some abandoned packages from time to time and once in a blue moon you get a dependency that doesn't install properly. When that happen you post a comment on the AUR or flag the package and it's solved in a matter of days most of the time. It's surprising that such a system would work so well, but it does.
This will make that device so much more usable.