Few thoughts:

1) I love Santorini -- we went last year and while we aren't going back for our honeymoon, it's definitely on the short-list. There will be a short window when it seems that SPG hotels like Mystique will be available temporarily at Marriott as Category 8 hotels which means it **might** be available for 40k/night plus 5th night free. That being said the other good option is if you have the Citi Prestige, go the 4th night free night at one of the boutiques (we did that and stayed at the Astra Suites and loved it) and utilize the Marriott/SPG to transfer over to airlines (see bullet 3)

2) Use AA miles for Maldives ---> Bali. Will only cost 40k/person in J and believe you have a choice of either MLE - DOH - DPS or MLE - HKG - DPS

3) Use AS miles for Bali ---> US. Ideally pay out of pocket for DPS - SIN or CGK and then grab Japan Airlines for SIN/CGK - NRT - DFW which should come in at 65k/person for business class and gets you straight back into Dallas. You can also add a stopover in Tokyo if you want to spend a couple of days there on the way home

4) Use Chase UR for PH Maldives

5) Use AMEX ---> Aeroplan for US ---> Europe. Should be 57.5k/person in J. You can fly any *A but they do pass on surcharges so ideally look for UA / SAS / LX. You could also splurge for LH F (if available within T-14) which would be 80k/person but that carries some hefty surcharges. You could also look at AMEX ---> FlyingBlue to grab Delta Saver awards (anything that shows up as 70k on Delta.com) or AF awards. In all likelihood you'll need to fly to ATH and separately purchase ATH - JTR - ATH tickets. Shouldn't be a big deal because those are cheap but do be aware that the flights are frequently delayed because of winds on the island (if/when we go back, we will be taking the ferry, we are still fighting with Vueling over a year later for EU261 over a canceled JTR - FCO flight).

6) Santorini ---> Maldives looks like the difficult one in all of this. AA is doable at 42.5k/person in J (would need to transfer some SPG/Marriott to cover) and you could use QR again (ATH - DOH - MLE)