Agree that Tokyo Banana is nothing special. Agree that exotic flavor kit-kats make for nice cheap gifts just for novelty purpose, even if they're not anything special. As I wrote elsewhere recently, those special-flavor kit-kats in Jpn used to be better 10-15yrs ago. They used to have really good ones like jasmine and espresso. Now they're nothing special. I don't buy them for my own consumption.
Royce is great, if you buy their "nama choco," the kind that's sold refrigerated. Personally I actually like the nama choco from MonLoire better, but those are harder to find in Tokyo area. Other than nama choco, Royce is nothing special. But nama choco can be a pain to take home and stress-inducing due to concerns about keeping them cool throughout your trip home (even if they give you icepack), unless you've got some space in your carry-on and it's winter-time.
Kobe Fugetsudo (not to be confused w/ Tokyo Fugetsudo)'s L'espoir Gaufrier is great.