So you are wanting to build a new init system from scratch and you haven't taken the time to see all the stuff that already exists? I mean if this is just a project you want to do go for it but if you are seriously trying to build something for others you know whats out there and why people choose one over the other beyond just systemd and sys V.
But in fairness Davin McCall has done more than most. There is a short writeup of xyr opinions of various systems, that comes with the Dinit source code. It gets a number of things wrong about several of the systems and does not go into as much depth as, say, the Debian Technical Committee members did. But it does show that M. McCall has at least looked, just as xe states.
Honestly, my impression is that this is how everybody that did something widely adopted acted.
I don't think it's desirable, bu there may be a problem with taking your time to review everything out there.