As I understand, cm theme engine is not yet ported to nougat ROMs. So, as as @_Jackie_ said, it will be really really difficult and may-not be worth. Anyway, its your choice and decision. Good luck...
It may be possible
-Removing substratum completely is easy
-Implementing cm theme engine is quite hard as i will have to figure out how it works and the files and other stuffs releated to cm theme engine.....may be some porting will be required as cm doesnt support cm theme engine anymore for cm 14....and its not necessary that ported will work.
-I might give it a try if lots of people want that not for a single person