As other posters have said, it is just a classic and for me personally it is nostalgic. I remember riding it as a little girl in 1980, and I remember taking my DSs on it on their first trip in 2005. It is now nostalgic for them too. We have ridden it on every trip since. For me, I love the black light effect, flying over London, and seeing the story of PP before my very eyes. As another poster said, it just touches the sweet part of my heart that makes Disney magical.
All of that being said, if I didn't have the emotional attachment to the ride I am not sure if it would be worth the FP+ or the extra long wait in line. By best advice is to find your own personal nostalgia, your own Disney magic, and to build your own memories and traditions. If you think that includes PP, go for it. If it doesn't, then have fun finding your own magic!