Putting technical considerations aside,
Peer to peer markets will work exactly for what and exactly how GLBSE has shown them to work (a centralized market run by undistinguished members of the general public being indistinguishable from a peer to peer market in any practical sense): a collection of the useless, the dysfunctional and the pointless taking turns to become fashionable, thus copied, thus reinforced by "social proof", presided upon by many idiots of which some are useful and a handful are outright con artists, generating an ever increasing quantity of drama per BTC.
There's a reason lemon laws have to be introduced in any market where the costs of discovery are high and the actual value per unit variable: buyers are willing to offer "average" prices, sellers knowing this will never list anything of above average value, as a result the average spirals down. There's always going to be need for a place where the above average can be listed, and that's the end of the p2p market as a serious venue.
P2p works well for money because money is fungible. It's a good idea, much like flight is a good idea: for some applications. Not at all for anything and everything under the sun.
It's in no way a solution, other than for the purpose of continuing to enable the unqualified and inept to scam outright, or to earnestly work towards some innocent end while ultimately losing people's money.
People were trying to use similar approaches after GLBSE fell in, the flurry of related posts since BTCT fell in and worried shareholders are left wondering if its friends are going to follow suit shows it's still a veritable hope-mirage. None of this has any bearing on the facts.
GPG contracts.
Security that isn't based on the limitations of a "slick" website.
Actual IPOs from actually planned out,
accountable entities. Yes, there's a fee. You're paying for that which works, which in the end is all that's worth paying for. No, I'm not especially nice in that In-N-Out Burger sort of way (though I'm just PR, you don't have to deal with me at all to use the exchange). The lies, the sugar-coating, the beating around the bush, is exactly for cheap food service and has no place in BTC finance. Plenty of people have thrown a fit over these facts, I'm sure plenty of people will continue to do so, and will continue to lose their money. MPEx will be right here.
You are on the right track in terms of looking for problems and trying to conceptualize and present solutions, I don't mean to discourage that at all. It'd be a good idea to devote more time and resources to
reading up and getting a better picture, tho'.