It's lovely! There's very much to love about this photograph.
The one remark I will make is this: when the subject is not making eye contact with the camera, an "environmental portrait" is sometimes a good idea. Include more of the surround and show us the context. This comes out less as a portrait and more as a photograph of an object that happens to be a man -- and it's a marvelous photograph of that -- I just don't feel that it's a "portrait" per se. We get no sense of interacting with the subject, or the subject's environment.
That's sort of abstract jibba-jibba isn't it? Maybe something in there makes a germ of sense, though.