Playing Devil's advocate here:
I think that there would be growth issues in this model. On paper, it looks doable (and different). But there are some usability changes.
Exchanges are "fast". Auctions are "slow". There is a reason why eBay cant grow (Not exactly the same thing, but you got the point).
Yes, I have got your point. But we don't propose high speed transactions.
We what to allow people to reach consensus (demand/supply) on price through bargaining on it in auctions.
This offer is unique for p2p types of crypto exchnages.