My question is why are there so many different styles of Aikido? Don't they all originate from O'sensei? ....
O Sensei didn't invent anything new, he studied various martial arts and then decided to 'create' aikido. Ueshiba sensei studied Aiki Jutsu for over 30 years along with Japanese fencing and many other martial arts.
Like many modern martial arts it has it's origins firmly based in another.
Jujutsu -> Judo
Kenjutsu -> Kendo
So with a martial art that was highly ecclectic in its conceptions and creation. Why even try to look at all these aikido 'styles'.
Instead, if you are seeking something a little more true to the roots, then with all respect, try jojutsu (etc) for weapons and maybe aikijutsu.
Split the discplines back into their original forms and then maybe a little clarity will help you choose the right path.
Just as O sensei did.