Dynamic suggestions for exclude directories
I find that Disk Usage Analyzer is fairly convenient to discover what folders would be nice to exclude. It is very easy to see what takes huge amounts of space, and to exclude them if they are not personal data per-se (i.e. easily creatable again) like toolbox (throw-away) containers, or some other application data that can be downloaded later as part of the re-installation, through the app.
There is the appstream:
URI which is supposed to open Software and propose to install the software indicated with e.g. appstream:org.gnome.baobab.desktop
. On my side it turned out to not work much (it was loading the page then indicated it didn't "support this operation"), so maybe a link to https://flathub.org/apps/details/org.gnome.baobab would suffice instead?