It’s not horribly complicated. I have a single 3 line script capturing the current state of my homebrew, flatpak, and rpm-ostree state that runs before Pika Backup backs up my entire home directory.
You have 5 bash scripts and various dotfiles. That sounds a lot more complicated.
Bazzite is really not much different to any of the atomic fedora distributions.
The only thing more complicated about immutable Linux is that you have to rethink how you install packages a little bit, as you’re generally using installation methods that offer isolation from your base operating system.
The big upside of this is that essentially all of your modifications are confined to your home directory, and of course system updates and rollbacks are trivial.
The complexity is hidden. I don't require all the gumph. I just gave bash and a Debian install. Pretending the rube goldberg machine isn't one because you've hidden it behind a facia doesn't mean it isn't one.
When all of that complexity doesn't work (which sooner or later it will), it will be more difficult to fix.