It turns out that with Tuesday closures for a lot of the Museums we want to see, and the 2 day Museum pass requiring consecutive days, our best approach is to purchase tix in advance for where we want to go, and print them out at home. Has anyone done this successfully and skipped the long ticket lines?
D'Orsay and Orangerie' have a joint entrance ticket option and the Louvre provides for scheduled admission.
I don't know how else to do this with a Monday arrival and Thursday departure for Greece.