I think your experience is limited. I chose my terminology very carefully.
The exercises I'm referring to in 1 are *not* techniques, in either aikido or Daito Ryu. They are exercises. They build the foundation on which techniques rest.
I apologize if you thought I was trying to tell you what you were referring to. I had hoped it would be clear I was referring to my own experience.
The article we are discussing sets up a dichotomy between creating aiki in kata (which is not uncommon) and creating aiki in a free application (which, Kimura asserts, has only truly been done by Sagawa and Takeda). I'm not attempting to invalidate your three levels, just pointing out that (in my opinion) a good kata-based system can serve the purpose of both your aiki-focused exercise and your Aikido waza-based kata.
Its interesting that you bring in the notion of aiki exercise since Kimura didn't mention that kind of experience in this article. Sounds more like people just trained kata at Sagawa's dojo, with Sagawa, perhaps, demonstrating free application from time to time.
P.S. Obviously my experience is limited. I started Aikido in like 1992, hardly trained after the first year, and didn't get serious about it until about 14 years ago. I've practiced Yagyu Shinkage ryu for not quite six years, and Daito ryu a meager four.