Another thing I feel would be a flaw is the inability to increase and decrease the money supply - something central banks often do with fiat money to stimulate the economy.

Most crypto currency seem proud even that they can only deflate … which is the worst thing for a currency since it will just result in hoarding and ever decreasing economic activity (AKA deflationary spiral) - at the end of the day, economic activity is what we want, it’s what put food on supermarket shelves, we can’t eat money.