You may find the area immediately around The Strings to be slightly reminiscent of the area around the Conrad - big office buildings, elevated walkways, very new, rather sterile. Unlike the Conrad, there's no "Ginza" neighbourhood within easy walking distance. There are actually quite a few restaurants in the modern development to cater to the office crowds, but it's not a fashionable center like Roppongi Hills. Transportation links are pretty damn good. You're right on top of a major station. And you can get around all of it with escalators.

Cerulean - The immediate vicinity of the hotel is no great shakes, but within a few steps you find yourself in Shibuya, which is an extremely colorful and lively area... it ranks right up with Shinjuku in terms of all things gaudy, garish, tawdry etc.. For getting around, Shibuya is probably a bit harder work than Shinagawa. Several places you find yourself hauling yourself up to elevated walkways to get across major streets. The hotel is a bit of a walk to Shibuya station. Some people say it's close - I don't see it that way. Maybe it's just the fact that pedestrians are forced over those walkways and under expressways to get around that makes the distance seem further to me.

ANA IC in Roppongi. Again, the really immediate vicinity is not super interesting, but its a short hop,skip ad jump to Roppongi which contains everything from the high-end leisure facilities like Roppongi Hills and Tokyo Mid-Town to the lowest of the low end of Tokyo nightlife. Connection to subway station - Tameike sanno is painless. It's more hassle to get to JR lines.