This is like saying "let's send people to Mars". You could spend hours describing the benefits of doing that, but your dreams will be crushed by all the difficulties of actually implementing it. Stability and decentralization don't work together, because any stability is achieved through a single actor acting as a stabilizer. Besides, if your system uses a centralized asset like fiat currency as its collateral, it will always be an inherent risk itself - fiat currencies can crash, or the government can block this decentralized system from accessing its centralized systems.