You've mentioned a few times that a new framework is firmly out of budget.
Might still be worth keeping an eye out though. They had a sale going a while ago for some units that were pulled for QA. If minor defects don't bother you it's possible to get a framework 13 for <1000€ if you're patient and a bit lucky.
I wish pinephone pro's weren't booty. Hardware switches to cut power to everything from the WiFi module to the camera sounds pretty hot in light of this.
Especially with Firefox and derivatives allowing you to run the webpage in an app-like way! I do this for everything from the public transit website in my city to financial sites.
nix develop
is going to change your workflow. Don't fear the flake my friend :)