Well, my subconcious is at it again. The other night I dreamt an unknown, never before aired series of episodes, perhaps planned for a new season that never aired, of the Brady Bunch where they took another mutli-part episode vacation (like the ones at the Grand Canyon and in Hawaii).
This one was "The Brady's European Vacation". I distinctly remember seeing a vacation montage moment (similar to when the Bradys went to the amusement park and they did a montage of them riding different rides) wherein Mike, Carol, Alice, Bobby and Cindy were all riding in a gondola in Venice.
I'm sure that Marcia or Greg (or both) would have had romance stories...Greg with a French girl, Marcia with an Italian boy (they would likely visit multiple countries on one of those whirlwind X countries in Y days type trips). Meanwhile, Peter and Jan would probably have a hokey subplot where they accidentally switch luggage with a spy and don't know they have a secret microfilm or something and are being tailed throughout their trip by a pair of bungling spies (perhaps Don Adams and Barbara Feldon in guest roles?).