@nebulon : interesting about Nextcloud
I used to have 4 x Nextcloud instances in my Cloudron server (different projects). 3 of them about 10Gb of files (other smaller).
My backups were working but slow.
Even after switching to 'better' VPS provider.
So after testing Seafile for a while, I have moved 2 of the Nextcloud instances over to a single Seafile VPS (with different libraries for segregation). The other 2 Nextcloud instances will follow.
I have nothing against Nextcloud and been very happy for it for long time. But if it is really only being used for file collaboration and device syncing, and you don't actually NEED the extra facilities it provides, my personal view is that Seafile is a better solution.
So would be awesome to get Seafile onto Cloudron.
But I'm quite happy running it on a separate VPS.