Battle.net running in bottles works Ok. I did have an issue with battle.net running under X for a while, switching to Wayland worked. Whatever the problem was seems to have been fixed

Btrfs will be fine, I use btrfs on a standard arch install, timeshift for managing snapshots, works well.

• Step 1: move data from files into a database

• Step 2: delete files

• Step 3: press release that we just deleted the files

• Google, probably