I think the koryu don't much care what you -- or any outsider -- think of them.
Well there you go, then. I heard exactly the same comment from some die-hard fellow students in Aikido back in the 1970's, so you're reinforcing an old idea. Any koryu that doesn't use the Yin-Yang, In-Yo, A-Un, Five Elements, etc., as a basis to the whole system (as Aikido and every "ju" art that I know of does) may possibly be totally outside of any interest that I have, so good luck to them and good luck to you. I'm personally not so fixed in my ideas that I'm trying to convince anyone outside of them, so please don't take umbrage in regard to what I think of as clinical discussions.