The answer to the OP's question is (groan), It Depends. Factors like where you can get award travel and what kind of things you want (upgrades or free trips?) are important. And some programs might look good on paper but be bad for seat availability or upgrade policy.

The big extra variable these days is what class of travel your tickets are in. If you're like me and always get the lowest fare category on your own dime then the picture looks different from those who can fly business at Y or a notch or two down.