Re: non-replaceable battery
I would have agreed with you a few years ago but unless the battery flips to hand-warmer mode in the first few weeks/months then it is likely to last quite some time. I currently have a Q10 which is still on the original battery but am likely to get a KEYOne because the Q10 is getting a bit battered and the USB connector is iffy but I want a phone with a physical keyboard.
If I have not needed to replace the replaceable battery in the four years I have had the phone then it disappears as a significant factor. Thinking back I have only ever once had an extra battery for a phone and that was a long way back when I was using a phone a lot and needed the comfort factor of spare power 'just in case'. These days I carry an emergency battery thing which covers that role for all my devices.