You also said something about adding a bigger motor, and that add a whole new layer to things as it means something other than a Sporty motor.
Have you just looked at custom Sportster frames?
yeah, the motor is long term though, and I looked at some frames, the softtail type that I want is pretty pricey though. This bike is my road tripper and I don't think I'd be happy with a rigid, and those are the only cheap frames I have found.