Re: Training at Hombu - is it worth it?
FWIW re: other places to train.
Kyoto and Osaka is quite well-supplied with aikido.
The Kyoto Budo Center has two or three groups of aikidoka's, at least one of which is led by a Shihan (sorry, don't remember his name) and trains three times per week. It was a very nice and open community there when I trained, and I can recommend it! Then there's the Osaka aikikai hombu dojo, which apparently have training some five times per week, though I never had the oppurtunity to train there.
Anyhow, Good luck in deciding where you're moving. I'll envy you no matter where you end up :-).