Do you have the issue tracker for kwallets issues? This is my first time hearing of these. Out of all the people I have given this to not one has had any complaints with kwallet, it’s possible these issues were resolved, although none of my users were using vpn’s.

libreoffice uses xwayland, so that’s really on them to fix and there are simple workarounds.

both of which are pretty quick fixes, kwallet can be replaced and the libreoffice issue is a toggle in the settings. I usually set people up and make sure they can do everything they need to, these issues seem very minor compared to the issues with cinnamon