I'm one of those people who find most systemd opposition rather unconvincing, but good luck to you anyway.

I was surprised by the fact that you'd actually removed the mount and device unit logic from your fork. In my view, the init/service manager (with its dependency resolver) is the correct place for something like that because services depend on devices and mounted filesystems being available. How should those things be handled, if not there? Udev-triggered units and systemd generators seem to me a very clean way of handling the problem while maintaining backwards compatibility with /etc/fstab and other configuration sources.