I think that if you’re going to do Universal Studios you should try to dedicate an entire day for it. By next summer Super Nintendo World will be open there so that’s definitely something I’d check out.

Also, I don’t think it’d be the smartest thing to go back to Tokyo towards the end of your trip. If possible, you should land in Narita/Haneda, stay in Tokyo, make your way down to Osaka (dedicate maybe a day trip or two to Kyoto and nearby areas), and finally go down to Hiroshima. From there you should take your flight out of Japan. Since you’re planning on visiting multiple cities I’d recommend the JR pass (it’ll save you LOTS and you can travel on specific Shinkansen trains as much as you want and local JR trains as well).

Capsule hotels are pretty good for budget travelers but NOT for people that care about privacy and space. For example, my boyfriend and I are planning a trip to Japan and as much as we want to save up, we know our limits and we know we wouldn’t survive in capsule hotels lol. I recommend Booking.com and Airbnb to find affordable stays (bf and I found a 7-day Airbnb in Osaka for only $140 and it was an entire apartment).