I think you have done some nice work here. I especially like # 18, 5 and 17. I am curious what the colors what it would look like when copies or faxed in black and white.
I think there is no problem about xerox or fax copies. The colours will be converted to grayscale (like here #33). And I think that most of the time the logo is used in colours (web, business cards, billboards etc...).