This question is not meant to address how you plan for your trips. I am more interested in your underlying motivation for visiting Europe and whether it is similar to your travel partners.
Are you intending to see the cultural sites primarily? Are you intrigued more by people and understanding their viewpoints? Are you driven by a desire to change the way Europeans view Americans? Is there something about getting that extra stamp in your passport that motivates you to visit a new country instead of returning to those you've enjoyed already?
I realize it may be easy to say "all of the above." But I would like to know if there is one reason that shadows the rest.