The big benefit to P is the upgrade certs you get as initial benefits and the two that come with the 20k threshold. Although Y/M/U fares can be pricey it's still cheaper buying one of them for international travel and getting an instant u/g than it is to buy Z, C, or J. The NA u/g certs are also useful when the domestic Latitude fares go on sale as they've done a couple of times this year.

Of course, a couple of quick easy trips to LHR or HNL would put the OP into Elite territory!