Very interesting idea. Have you heard about Basecoin and Seigniorage shares? They are trying to do exactly that: http://www.getbasecoin.com/ Are these coins securities in your opinion?
See: https://en.wikipedia.org/wiki/Liberty_Reserve#Criminal_inves...
Why bother using a convoluted blockchain stablecoin rube goldberg machine where you need to jump though several hoops just to use it, when you could use a service like venmo, square, stripe, etc? What use case would justify the need for a stable coin if not for evading the law?