Just got back. A few notes

I returned last weekend from a wonderful 2 week trip to Japan. My itinerary was about 7 days in Tokyo with a day trip to the Mount Fuji region (Chureito Pagoda, Lake Kawaguchi), and an excursion to Enoshima. I spent 1 day in Hiroshima, and the rest of the trip in Kyoto with an evening excursion to Osaka.

Some quick notes for anyone interested, and thanks to all the previous recommendations here that definitely helped!

1. Welcome Suica, which I got at Haneda was incredibly convenient to use for trains/public transportation around Japan and at convenience stores. Only thing is to make sure you use whatever is on it before you leave. As of last weekend, the duty free shop in Haneda terminal 3 was NOT accepting IC cards but the 7/11 was, so get stuff at the 7/11 before hitting the duty free. Note that 7/11 will not let you close out the IC card and then put the rest on credit, but you can close out the IC card and use cash for whatever is left. If you have any coins left, you can use those at the duty free.
2. The duty free at Haneda does not have a great selection of liquor or amazing prices, so if you want a deal on whiskey/sake to take home, get it at a supermarket or liquor store outside the airport. The taxes will not be very much.
3. I had 55,000 JPY cash for my 2 weeks, by myself. It was just the right amount for me, but I was somewhat frugal there. Of course, I had several meals and bought some things that was paid in credit card. Make sure you have a no foreign transaction fee card!
4. Be careful walking! I joked to myself that Japan needed more lawyers, because I almost tripped or twisted my foot several times. Sidewalks in Tokyo often have little ruts that are very easy to step in accidentally. Many streets in Kyoto have no actual sidewalk so you just have to stick to the side but be careful to look out for traffic and especially bicycles! It will be tempting to frequently look at your phone while walking to make sure you are going the right way, but do it carefully!
5. Be careful in hotel rooms! In most of the hotel rooms that I stayed at, the bathroom was slightly elevated or lower than the rest of the room. If you need to use the bathroom at night, you risk an accident unless you know how to step!
6. Enoshima was the highlight of the trip and I only went there because I'm a train geek and wanted to ride the Shonan monorail. However, the view of Mount Fuji across the bay at sunset was beyond spectacular. If there's a good weather day with few clouds, it's definitely worth the trip!
7. If I had to do it again, I would not book a tour to the Chureito Pagoda/Kawaguchiko area, but would just go to Fujiyoshida by public transportation on my own. The tour did not give a lot of time at Mount Fuji but gave 3 hours at the Gotemba Outlets (I think because it is very popular with Chinese tourists who love the outlet mall.)
8. Kyoto is amazing. Add in at least one or two more days longer than you were planning in Kyoto if possible. Each of the temples and shrines really is special and you will not have time or stamina to see everything. Going to Kiyumizu Dera at 6AM is a great way to start the day!