I'm glad that you got a chance to work with Akuzawa and Rob. It really does open up a whole different world, doesn't it? But at the same time it opens up the questions that you're asking yourself about continuing training.
If I choose not to do this training, I know there's something missing in my aikido. Again, other people might disagree but that doesn't matter, if I believe it myself. And if there's something missing in my aikido, and more importantly, if there's a very fundamental flaw in my aikido, then do I want to continue doing it?
The joy of Aikido will not go away by continuing with the added training. Yes, it will be a more difficult road, but there are always spots in that road that make the trip worthwhile. Always. And if you hold on to that which you love about Aikido, then how could the added training not eventually get subsumed by that?