Lots of good ideas here. For other reasons I use:

find /path/to/mount -xdev -printf '%p\t%y\t%s\t%T@\n' | zstd > /path/to/output_fs.tsv.zst

on a regular basis. For convenience I also munge the output into json so that it can be piped into gdu -f - for a very convenient tui interface; but you could also just pass -o to gdu and save the resulting json. Very convenient.