It doesn't help any that they're also butt ugly. Almost everyone uses a Sportster as a stepping stone to a Big Twin. Even most women, who may be a little intimidated at first, end up wanting a big bike eventually. The least expensive way to go would be with a rigid frame. Many purests believe that a rigid is the ultimate custom bike, and I would probably be inclined to agree.
Nothing looks simpler or cleaner than a well done rigid.
If you want the traditional, stripped down chopper look, this is it. Unless you are satisfied with those crappy looking aftermarket sissy bars or fender braces, some fabrication will be needed in the rear fender area. Rigids are impractical as hell and fairly difficult to sell, but damn, they sure look cool. Give Ted a call and start on that new bike right now.