Well, I agree that FPTP is a horribly poor reflection of real voter sentiments, and that a better system would be an improvement.
(Personally, I find the idea of "delegative representation"; similar to what they call "liquid democracy" in Europe, intriguing. Tho I think I wouldn't support changes in delegation between elections.)
But the larger question is - even if we have a system that accurately reflects voter sentiment - is the voting public smart enough to make reasonable decisions? Does the majority even care about the erosion of their liberties?
Just talking to my neighbors, there are a huge number of people who fundamentally don't understand or support the idea of "rights" at all - except for the right of a majority (50% plus one) to impose its arbitrary will on a minority.
Revolutions famously eat their young. And are bloody. Looking around the world, I see few places that are doing substantially better than the US. It is far from clear to me that a revolution would (a) succeed, or (b) result in an improvement.