Why not mainline it?

Linus has said in the past that he absolutely detests specialisation and doesn't want more than one scheduler in mainline. It's the same reason the "plugsched" pluggable CPU scheduler framework that went along with the original alternative schedulers, staircase, RSDL and staircase deadline was abandoned. Therefore it would have to replace the mainline scheduler en-bloc. As a hobby amateur coder working on a scheduler in one's spare time, there would be zero chance of creating something that meets all the criteria of trumping every mainline performance benchmark and feature to replace CFS.