I doubt you want to run Gnome on a system where you have to use busybox.

Also if busybox is not enough, a minimal systemd system will still be leaner and faster than the equivalent sysV system.

http://events.linuxfoundation.org/sites/events/files/slides/...

It's not just GNOME; an embedded device that acts as a USB host needs something like udev, and as I recall reading systemd has swallowed the hardware plugging notification systems, or was working on it. The success of systemd in getting single-user kernel patches that only make sense for desktops and systemd is most concerning, though. Linux is great because of its modularity; previously, if init didn't make sense you could switch to openrc, upstart, or others, without having to change the way you do logging, DHCP, hardware plug events, etc.