Omoto-kyo can be different in some ways from regular Shinto, and Ueshiba's personal interpretations can get a little different from that, so it gets complex.
Of that I am sure.
My interest in Aikido lies closer to home - I have no ambition to think like or be like Ueshiba. Still the beliefs of the old man seemed to resonate down to levels I am more directly involved in so your explanations do help to put things in context.
There is an Omoto-kyo shrine at Shodokan Honbu visited by their priests. Tomiki studied the works intensively and Nariyama for a time taught at Ueshiba M.'s old dojo at the sects headquarters. So it is there but luckily I don't have to worry about it too much.