Of course, I can understand why Data would want to be human. For instance, we have feelings and experiences that he will never have. It's not that he's lacking, not at all; but he has that curiosity that will never be sated such as what it's like to laugh, cry; have an emotional response to the moving chords of a song, or to even taste what he eats or drinks. It's not that he's unhappy with who he is, he's just wanting to experience the little things that we as humans so often take for granted.
Maybe, but I suppose he would be better off if he accepted that he isn't human, and that that's just as good. I mean, what are humans who are unable to feel like the majority supposed to say? I understand what you're trying to say here, and that's what he's obviously after, but my advice would be: try to better yourself, yes, but don't try to be something and someone you're not. You're perfectly fine just the way you are, and don't let anyone tell you otherwise.