I would create separate nodes for each piece of metadata within the scene you are loading, you can use a Node2D (or Node3D) to store a position (such as a spawn point) and there is a Timer node which can hold the time for a level.
Alternatively, under the node inspector there is an option to “Add Metadata”, which might be more along the lines of what you are looking for. It can be read with the get_meta function.
I backup to a external hard disk that I keep in a fireproof and water resistant safe at home. Each service has its own LVM volume which I snapshot and then backup the snapshots with borg, all into one repository. The backup is triggered by a udev rule so it happens automatically when I plug the drive in; the backup script uses ntfy.sh (running locally) to let me know when it is finished so I can put the drive back in the safe. I can share the script later, if anyone is interested.
It’s been added recently, in the form of External Libraries.
I did not know that, last I looked it was still in development, I believe.
Something that LVM supports but ZFS and BTRFS don’t, is the ability to reduce your storage. (That is, to empty and remove a drive from the array, without having to completely destroy the storage array.) As a home user without sufficient storage to have complete duplicates of everything, I find this an important feature.
In Settings -> Accessibility-> Touch -> Assistive Touch you can configure a small button the floats on the screen (you can move it around), providing access to all sort of gestures and functions one handed.
I haven’t looked into this, but in step 3 can you call the editor’s undo function?