Dave mate, I get that the points you raise are close to your heart but scrapping BMD? Come on fella.
The argument for it is actually pretty simple - take whatever the cost estimate is and double it, because that's what you're going to spend. See: Spurs, Dallas Cowboys, Los Angeles Rams. Then compare this to the cost of major redevelopment projects like the ones I mentioned (Fenway, Wrigley, Anfield).
Now, ask yourself how long it's going to take for the new stadium to improve the club's finances given the difference in price. These projects do not pay off in a timely fashion. They're vanity projects. They're more common here in the US because we permit teams to threaten to move in order to extort public financing.
Put another way - Levy may be tightfisted, but do you really think he isn't spending to improve a club that was a match away from lifting the European Cup last season because of his nature, or because he can't afford to?
Redevelopment is almost invariably the sane choice, and the venues I listed are as good as anybody's. There's no question that we need to do something, but one option will delay a proper squad rebuild a lot longer than the other.
Dave's just holding up a mirror to what's out there. I actually think he's right about Ferguson; the politics of the situation made it impossible not to keep him on, but forcing the manager to keep an assistant not of his choice rarely works out well.