[bitfolk] Filesystems/volume management for home servers

With the discussion about RAID 10, that got me back to thinking about
better/alternative system to my current RAID1+LVM+EXT4 setup on our
Linux home server and I'm looking for advice from other members.

Currently we have 13.6 TB of storage (a lot of which are photos by my
semi-professional girlfriend, and videos from our wildlife cam which
produces about 15 - 20GB of videos a day [email me off-list if you want
to want the URLs of my fledgling Youtube hedgehog and bird channels]).

There is some amount of file duplication, for instance where I have
stuck old backups (copied files and folders, not tar/compressed
archives) on there or photos/videos have been copied to different
folders (e.g. to categorise), so filesystems with built-in deduplication
(like I believe BTRFS has) would be nice.  However my main priorities
are: maintaining data integrity, ease of administration, and really a
sub-category of that: ease to expand or shrink and reallocate storage as
required (if necessary - quotas are not required, but crashing due to a
full disk is to be avoided).

For years I have been looking at BTRFS, but it's never sounded 100%
production ready to me (although I remember that at least one distro
made it their default fs).  Andy's mention of ceph and stratis were
something new to me, but I'm not sure if they are a bit much for a
single server, and I've no experience with ZFS, but I think I read about
some disadvantages that put me off a few years back, but I forget what
they were now.

Anyway, what do/would you use for this sort of scenario/requirement or
what are your experiences with suitable filesystems for my
requirements?  Just to be clear - I want to ensure that a single disk
failure is very unlikely to result in data loss.  Also, all disks are
currently the spinning disk type, so any features that takes advantage
of SSDs would be wasted.

Thanks

Gavin