This is great. I have the Fairphone 4, which does have a couple of issues, but the fact that the battery can be replaced will increase the usable lifespan of the phone.
I have a Pixel 2 used for messing about with Lineage, but the battery only lasts fifteen minutes, but is otherwise still a great phone. If it was easy enough to swap out that battery, I'd probably still be using it as my main.
I really should give this a go again. I did run it for a little while, but switched to the paid hosted version as I want to have family tied into this and ultimately not be responsible if things go to hell. As long as I have decent redundancy / backup plans in place, it should be alright, though!