I would say that perhaps you are being a little too restrictive in your usage of a number of the terms. Taijutsu goes beyond the Waza and sometimes much less depending on who is using it. Like you mentioned in the term Kata, we have much latitude in how these words are used and the format in which they are used or the sentence in which they are used. For instance, the term Kihon will describe different things when used at different levels of practice/Keiko. What is your basic practice and what is my basic practice will differ if we differ in rank and principles being practiced. Depending on how we practice Ki-no-nagare, there may be no attack or attacker. It could also be Henka-waza practice or Kaeshi-waza practice which always be done using Ki-no-nagare. I would say that the term Ki-no-nagare should be used more for the principle than for a form of Keiko.
I would also differentiate between Jiyu-waza and Randori with Jiyu-waza being the Keiko and Ran-dori being the state in which you practice. It is much like you can do Henka-waza practice during the execution of Tanto-dori.
I guess the usage of these terms have become a little more restrictive these days to avoid confusion but I kind of like the old ways a bit. If you become a little too restrictive in how you use these words, it will confuse you even more with the broader usage by the Shihan when discussing things outside of the Dojo or with people from different Dojos.
I'm really not an expert in these things but I know that when translating into English for some of the Shihan, I have found that their usage of these terms is a little less restrictive and I have to be careful to try and clarify when turned into English so I use the terms myself, a little more restrictively, when doing those translations during seminars. On the other hand, I could be doing the translations all wrong. Oops!