I stayed at The Gate hotel in Asakusa, which I thoroughly enjoyed, on my last trip there. Liked the neighbourhood - I'm not interested in glitz and high-end stuff, and it was very well connected. You can get the train direct from NRT to Asakusa Station (the Keisei Limited Express) which delves into the metro. There are lifts to take you to street level. Easy enough if you're Black-Catting your luggage and don't mind the longitudinal seating.