Best Star Alliance program to join for USA-Europe travel?

Best Star Alliance program to join for USA-Europe travel?

maybe aegan?

but only if you can manage to take the qualifying flights with them

Many variables here. How often? Which Star Alliance carriers do you usually or intend to fly with? In what class?

Wouldn't recommend Turkish Airlines as they recently overhauled the program and you get points based on the amount of money you pay and it is all pretty dismal.

I'd say, take a look at Lufthansa. They have a pretty big footprint as far as Star Alliance is concerned and because they own a number of European airlines, you get a lot of points from a larger number of airlines.

Which country do you usually fly to?