No regrets over last trip, but only because the last trip was a spur of the moment "bring back the magic" trip.
I have regrets over our October of 2002 trip. We brought my in-laws and treated them to accomodations at our home at Boardwalk. We got a two bedroom and gave them the studio side which they never moved from. I envisioned it that they would use it as the bedroom, we would use the master bedroom and we would share the common area. But they stayed in their own room the entire time. They watched TV in there, ate in there, etc. We had all of 1 meal in the room together (but we did eat out a few times with them). They wanted us to plan everything but then criticized most of what I had planned. I was trying so hard to make them happy that I became miserable.
Thank God for my wonderful DH who suggested that spur of the moment trip in December. We were out of points so couldn't go back home, but we did get to experience Coronado Springs. No it isn't DVC, but it was fun for this trip. We have since gone on the DVC Member Cruise and that was WONDERful as well.
Now we have a May cruise and his parents are coming again (planned well before October). I'm lowering my expectations of what I have to do for them and I'm making sure that we enjoy ourselves. We've picked our excursions and we are making them pick their own (know they won't do at least one of the ones we are doing).