So, one suggestion I just saw was that instead banks could insist on insurance for the value dropping by up to (say) 10%. If you can afford the 10% deposit, then you're fine, otherwise you're paying a little more on top of the mortgage to cover the bank against the risk of lending to you.
Is there a massive flaw in this plan? I mean, obviously it's unfair on people who earn less or don't have rich family to give/loan them deposits. But other than that?
Original post on Dreamwidth - there are comments there.