Thank you a lot @mosen, for the detailed reply. So as long as I stick to android, I shouldn't need to fix a broken persist, that is good to know. If I want to be on the save side, I could fumble with the Qualcomm QPST gui to create some backups, but they should not be needed.
Concerning the recovery, I was not able to get a menu in it, only for the bootloader. But I guess I will stick to the official root and flash instructions, so I may not need this, hopefully.
Just for anyone's information, who may come across this post and needs some input for using edl on windows:
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