Wirelessly posted (BlackBerry8530/5.0.0.601 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)

Here's something else for the OP to consider: AA permits free stopovers at the North American "gateway" on international awards. So for 20,000 miles per person, one could get LAX-JFK (stopover) - Europe, as long as the LAX-JFK leg were flown after October 14. This would even permit the JFK-Europe portion of the trip to be flown during peak season at no extra charge (assuming that MileSAAver seats could be found). Of course, this approach would require getting from and to JFK, but that might be worth it for the miles saved. (And with advance booking, Megabus/Bolt Bus can be pretty cheap between NYC and PHL.)

If the JFK stopover strategy appeals to the OP, then perhaps it would be best to use the CO miles for a one-way award from PHL to LAX, and then use the AA miles for LAX-JFK-Europe-PHL. (CO will begin offering one-way awards later this month, I believe; until then, CO miles can be transferred to UA, and then redeemed for one-way awards.)

And if the OP's girlfriend decides to sign up for credit cards, remember that people have reported successfully obtaining both the Citi/AA Visa and Amex (for a total of 150,000 bonus miles) if both applications are submitted on the same day, one right after the other.