Well.... there are currently only 2 US fighters in the Top ten lists. So I don't know where you're getting bias toward Americans.

Certainly Chris John should be ranked above JMM, if you accept that he lost I believe he'll get some recognition if he beats Juarez convincingly or gets a decisive win in a good fight. One thing for sure if he wins, is he'll be setup to make a lot more money in his next fight. Isn't that what it's really all about? Even the Philippino crowd will back him since there isn't a way for him

Is there really a non-bias way to rank a P4P fighter with active fighters? You could have a polling system like in American College Football, but then it wouldn't be authoritative to those that come up with P4P list so then they wouldn't like it.