Nothing wrong with that of course. There are advantages to making your own things.
FanFicFare isn’t perfect either. For cloudflare it supports using FlareSolverr, but from what I heard it doesn’t always work well. Alternatively it can open the pages in your browser and grab the content from the browser cache.
I mainly like that it’s available as a Calibre plugin and that it supports just about any fan fiction site.
Afaik this is only a problem if you use RAID 5 or 6. Otherwise it’s as solid as other CoW filesystems like zfs.
https://btrfs.readthedocs.io/en/latest/btrfs-man5.html#raid56-status-and-recommended-practices