What exactly is "awkward" about 16 (not 15) colours? Windows itself only has a palette of about 16 colours, and it never seemed awkward to me. Websites usually design for somewhere between 3-5 colours, but never much more than that. Certainly 16 sounds enough if you're going to make a sane looking theme.
That said, "more colours" has been suggested
before, a few times in fact. The search feature in the forum can help you look at the discussions and possibly chime in on those, if you have something new to add. Until then, it's up to Khaled to take this on.
