I use FreeBSD for my website and I’m actually pretty happy with it, the simplicity is a strong selling point.
It does feel sometimes like the documentation is written with a lot of assumed knowledge though, which makes it difficult to know what terms to use to find what you’re looking for… e.g. figuring out how to do major version upgrades did not feel straightforward.
I go with characters from Super Mario, eg Luigi, Bowser, Yoshi. I like them because they’re short, easy to type and memorable.
In case people don’t know, https://namingschemes.com/Main_Page can be a good source of inspiration.
I used rclone to get all my photos down, then I used Immich’s bulk import API to get everything into Immich just yesterday. I did about 14k photos.
Take note of the limitations of rclone though, it won’t get the original full resolution - https://rclone.org/googlephotos/#limitations you need to use Google Takeout to get full resolution.
Depending on your comfort level and setup, you could use LVM. Then the differently sized hard drives wouldn’t be such a problem.
Or if you want a much more complex situation, you could set up Ceph. It will also give you redundancy, but it’s a really steep learning curve.
Perfectly server grade, the way the manufacturer intended