But hey, as I said, I don't care how this is achieved. If a light client can give me the same sovereignty, I don't care, as long as it does. As long as I have to give my explicit consent to a rule change, I'm happy.
This sovereignty you mean is mostly an illusion. The real power you have is that if the rules change in a way you don't like, you can sell your coins and go use another system that works the way you want. this is not substantially different from just sticking with the old version. The specifics do differ though. Whether you're actually validating things yourself only affects whether you have to trust what others say about the system or if you can verify it for yourself.