I'll have to be selfish as well and say I truly enjoy the Parks solo much more than I do with others. For me, a trip to Disney World doesn't happen all that often, so when I do get to go, I want to hit every attraction...even the ones I'm not that fond of. I also want to video tape everything, as good attractions seem to be killed off far too often now.
I just returned from a trip to Disney World yesterday. It was the longest I'd ever been there (7 days) and yet I only accomplished about 3/4 of what I did with 5 days in 2000. The reason: I went with some friends and their kids. The kids were more about whining, pin trading, and wanting to eat. After four days of accomplishing very little (and trying to ignore the non-stop fits and fighting of the two girls), I finally began breaking off from them to let them do what they wanted to do, and allow me to do what I wanted to do. I still didn't get to a number of things I wanted to go on, but the last half of the trip was by far more memorable to me than the time I spent with the group. Maybe part of it is that I know I've always been more of a loner than a group person. Also, I don't like trying to tape something and having to constantly listen to "Ooh, look at that!" being shouted into the microphone of the camcorder. Another part of it is that I am a go-go-go type of person at a Disney Park. That is a vacation for me, not lounging on a beach, not browsing through shops. Very few others I know feel the same way, so it just makes sense that I go it alone. My wife knows this about me, and tends not to go with me to Disneyland when she knows I'm on some kind of mission.
If you do better in groups, that's great. You're a stronger person than I. But there are those of us who function better alone. While I do like to see other people's reactions to attractions I know and love, I tend to enjoy myself more at the Parks when I'm solo. But then, I'm weird.