>>todsac+(OP)
I would like a comparison with runit, which is a
very minimal but almost full-fledged init system. I see many similarities: control directories, no declarative dependencies, a similar set of scripts, the same approach to logging. The page mentions runit in passing, and even suggests using the chpst utility from it.
One contrasting feature is parametrized services: several similar processes (like agetty) can be controlled by one service directory; I find it neat.
Another difference is the ability to initiate reboot or shutdown as an action of the same binary (nitroctl).
Also, it's a single binary; runit has several.