Best Of

Regarding taxis, when we left the hotel, we asked the doorman or concierge to get the taxi (often waiting out front) and tell him where we wanted to go. If at a restaurant and returning to the hotel, ask the hostess to get the cab for you and ask them to tell the driver which hotel. Also, tell them you need a cab that accepts credit cards.
Also, at any hotel, ask the front desk for a business card. It will have hotel name, address, etc in both English and Japanese. You can always show that to a taxi driver, or someone else, as needed. None of this is difficult.
And Tokyo is a very safe and walkable city.

There is no guarantee that the taxi driver accepts credit card, most do. At some locations, it may not be easy to find a taxi.

It's quite easy to buy metro tickets there. I'm not sure if Tauck still uses the Mandarin Oriental but it had an ideal metro stop because it was so easy to use. After a lot of walking the first day we used Tokyo Station's metro to get back to our hotel. It is huge; we felt like we walked miles underneath to get to the tram. After that, before and after our Tauck tour, I made sure that transfers were at the smaller metro stations. That worked much better.

To each, their own. I liked Tokyo. It waas c lean and offered everything you'd expect in a large city. I found Kyoto to be way overhyped as a beautiful city. While there were some nice areas, I thought it was ugly, for the most part, and the Philospher's Walk was nothing special either, despite the hype.