I honestly don't use my phone much either, it's as you say, mostly for text based messages.

Luckily I don't get spam calls because in my country we have pretty good privacy laws still:

like my number is set to private and I'm on the "Robinson" list, and if someone calls that's not in my contacts list I don't pick up. Cold calls is how they get ya, and once they know there's someone picking up, it's like sharks smelling blood.

The app I use the most, besides my banking app (which I've confirmed works in waydroid aka LineageOS), is probably the Lidl app 😂.
I do still use Google Pay quite a bit, but I'm fine going back to card. I don't even know if NFC works in LineageOS or /e/OS.
And like you said, as long as the phone can do some GPS stuff for navigation, that's mostly all I need. And browse the internet (IronFox) every now and then.