That sounds reasonable. The train trip is one-way, I assume. Then you would fly from Osaka to Okinawa and return to Tokyo?

That $255 is a good fare.

Kyoto and Tokyo are not that hard to get around. I'm just as illiterate as you are in Japanese characters and we did fine. And the Japan Guide website tends to have good information on each city and links to helpful sites.

I'd add a day in Kyoto. We had five nights and need to go back. It's a really nice city.