i would say that a white short IS more choshuv, and the goyishe world is the proof. would you wear a tux with a blue shirt? when was the last time you saw a president wearing a colored shirt in any kind of presidential setting? i can go on…
as for the question about whether a ben torah should wear a white shirt…i say lav davka. i went to chafetz chaim…i dont buy into the whole white shirt thing. i believe the rosh yeshiva;s criterion was that one looks elegantly conservative…or conservatively elegant…i dont think anyone really knows which 😀 and that can easily be achieved with any kind of color combination. and yes…i wear pink and lavender shirts 🙂