Interesting to see that you came back to expand on a nearly 10-year-old thought. I'm just curious was to what is being burned in your hypothetical: is it BTC or an entirely new coin? If its the latter, it means that you will have issued the entire supply at the genesis block, which leads to distribution issues. Perhaps I'm not totally following your idea but when implemented correctly, PoB has the capability to be the fairest consensus mechanism there is.