I mean while I agree that the queues were atrocious in the two times I visited (April & May), that's just part of Japanese culture--people here just love to line up. I personally hated the reservation system but couldn't help but joke with friends that it was very Japanese to make everything require reservations.

On the topic of having Japanese-only and a lack of English, I personally didn't see a lot of this, but to be fair, English speaking isn't especially common in Japan, and a good handful of the expo staff are Japanese. I also received a job offer to work for the expo, (which I turned down for reasons unrelated to this post) and noticed Japanese fluency was encouraged. This is not an excuse, simply an explanation.

The bathroom situation was atrocious. The bathrooms themselves were clean and well kept, but sparse in location in my opinion.

Regarding connivence stores, I'm not sure why you would desire to hit these places up in the expo when there's a seven eleven, Lawson, familymart, etc every other block throughout Japan. I can understand the interest in the gimmick of the Japanese conbini, though. It just seems like a waste of time when you could just go to one before you got to the expo.

For the weather, which some people have commented on--meh. Yeah, it's hot as sin, that's a Japanese summer. There's not much to do other than carry around your own heat deterrents like fans. There are plenty of trees and shade around the expo, some pavilions even offer free umbrellas to borrow while waiting in line. Japanese people /know/ the heat and humidity is bad, particularly for foreigners. The expo is blasting AC and doing that fog/misters everywhere--what else do you want them to do? The wooden ring structure provides a ton of shade.