Depends on what your needs are. If you want/need the extra features provided by Joplin Server (multiple users w/ administration, share/publishing, increased sync performance) then Joplin Server sounds ideal. Otherwise if you just want to maintain a simple WebDAV that you can use for other purposes than just Joplin then just stick with that.
Honestly I would just install the Simple Backup plugin on your local machines and configure them appropriately for the use of that client (i.e. I maintain more backups on my primary machines than I do on a dying Windows laptop but still have one there).
It produces JEX files which contain all your data and if you somehow lost literally everything else you can just set up a new sync target and use the JEX to restore everything.