If I may Abasan, I'd like to try & answer one of the questions you've asked.
Soke Gozo Shioda did not disagree with
O Sensei, more so it was a difference in the manner in which he conveyed his aikido. Shioda Sensei believed, and taught, that there are very many elements by which one learns & develops their own aiki. One method Shioda Sensei employed was to develop a formal manner to teach body movement, this is called Kihon Dosa or basic movements. In Kihon Dosa we have six different movements which teach people how to use the body as a unified entity. Ki, in the performance of Aikido techniques, is actually the culmination of several aspects of correct posture, balance, timing, breathing and the use of focused power. In Kihon Dosa we hope to build the foundations of all the above mentioned aspects of body movement and finally to be able to move the whole body as a focused element.
I'm afraid I cannot comment on the second part of your question, I've not yet had enough experience with Aikiki to make that kind of comparison. I do hope that I've shed a little light on the first matter though.