I ran a Tor relay on one of my spare servers for a while, and my god did that thing get port scanned. Even two years after I stopped hosting the relay, it was still getting pinged every 5-10 seconds (while my other servers tend to get pinged “only” once ever 20-30 seconds).

I use Nextcloud, but as you said it’s a bit big, and with each update it’s slowly turning into more of the entire G-Suite.

I’ve used filebrowser, but be aware that until just a few days ago, it gave out access to a shell. Even with that turned off, I’d be very weary of allowing access from out of the VPN. I had a server pwned with filebrowser appearing to be the vector, and to my memory console access was disabled for the account most likely breached.