See FF! You've much talent! Look how you've analyzed this possible aspect of a D/s relationship. These are all very good points and questions. I'd lot to try and answer or address a few. I agree with you in many ways. Additionally, as with any aspect of BDSM, contracts aren't for everyone.
However... I'm working on a holiday gift for my Mistress. I'll get back to this when I can. You've my word on it.