my list is the same as yours (minus android auto) and i've been wondering the same thing so i have decided to offload the capabilities that i need on my current phone while tethering it to my new lineage or graphene phone.

it seems that graphene is more secure, but i hate google with a fiery passion so i refuse to support them in any way including supporting their second hand market. i've also NEVER had good luck buying second hand personal electronics so it would be foolish for me to do it again. also: my goal is to de-google and my privacy threat is the local police and ice; not the cia, nsa, the rest of homeland security or mossad; so that makes both graphene and lineage work for me.

on the other hand: lineage supports more devices, but i looked the other day at the most recently released phone models and pixels top that list too; so it seems that going w a pixel opens to door to letting you use both graphene and lineage if you decide that you like one more than the other.

i was going to purchase an e/os device from murena up until a few weeks ago until its ceo showed his stripes in public and made he clear that he's thinks that only criminals was this sort of security.

Yes the unverified apps thing will affect you no matter what. It’s not getting better any time soon. There are a lot of reasons for that.

You can’t “de-google” if you are 100% married to googles navigation service. It’s gonna become much harder to avoid play services (the google play store and all its telemetry) if you need a banking app and teams even if they seem to work now because the “reasons” above.

Other people have said that “privacy is a spectrum” in response to the following unconventional advice, and that’s true! Your conception of privacy may simply be getting away from the default apps and keeping the play store! Just keep that in mind:

If you’re actually gonna do any of the things we consider phone stuff on your phone, in terms of privacy and security it goes graphene > appropriately configured ios > a big gap > everything else.

Maybe consider switching. There isn’t a big cost difference anymore.

Speaking from experience with both android and ios platfoms including many custom roms and the alternative repos/app stores, it’s much, much easier to stay as private and secure as possible on ios.

Teams works fine on GrapheneOS.

I recall Google Maps working briefly before I fired it in favor of buying a dedicated hardware map solution.

If they do work, which De-Googled OS should I go for?

Depends on your needs, I suppose.

All the options you've listed are an improvement over stock.

I had an old spare pixel to try out GrapheneOS, and it was faster than my newer phone, so I started buying GrapheneOS-ready hardware from then on.

I put LineageOS on some other hardware, and I miss some privacy features, but it's still pretty nice.

Lastly, if I install another OS and regret it, is it possible to install the stock OS again?

Yes. There's instructions to take a back up, at the start of the process.

My plan was to fall back to eOS or LineageOS if I hated GrapheneOS, but it's been lovely.

Edit: Also, what happens after Google's "Unverified App" decision has passed, will this affect these alternative OS?

That's all part of Google's app ecosystem. Install F-Droid or Droidify, and you'll be immune to all that. Aurora may work as well, but usual disclaimer for Aurora - it relies on Google and might break at any time.

GrapheneOS has made public statements GrapheneOS itself is unaffected.