I love to hear about this project, especially since I believe, that BTC is about to die soon and there have to be alternatives independently from BTC.
The only thing I find questionable in your concept is the trust factor. Trust has so many factors and is horribly complicated to calculate. There are new concepts of P2P exchanges (like Altcoin.io) that are based on Atomic Swap (or other alternatives for P2P exchange), which eliminates the trust factor at all. I think, this would spare you of the hard (or even impossible?) undertaking of making trust a calculable number.