As someone that is also moving away from a proprietary router / APs - the one issue I had with OpenWrt One is there are just not many good sources to buy it from* so you end up paying an extra 20% in shipping (at least if you live in the US).
It is super appealing though, as you could buy multiple and they should work as decent APs as well. Some popular APs have a bit more involved install process for OpenWRT which might be worth avoiding.
Another router to consider is NanoPi R4S (4GB version)
OpenWRT Page:
https://openwrt.org/toh/friendlyarm/nanopi_r4s_v1
You do have to load the openwrt firmware onto a microsd but that process is beginner friendly.
*granted I have not checked in a few months, this is subject to change.