I only discovered Pink Floyd a little over a year ago when my partner enlightened me. I have only listened to a few so far (Meddle, animals, Dark side and some of the Wall). I love Dark side, the way it all fits together from start to finish is amazing..
My partner remarked last time we went observing that we should have had some Dark side playing - it would make for a serene observing experience. So I think a PF star party is a great idea