**** To address your escrow suggestion: I am the one with BTC , so I am the one that has the RISK of losing not you. Even after a trade you can charge back and there is nothing I can do about it. So dealing with PP at all with digital transactions have no protection.
I think anyone should only take those amount via paypal which for which amount you can trust that person, and for paypal it is same either anyone take first or last. Both are same as it can be reverse.