Although with Blumlein I have noticed i will need a taller stand to use at festivals. The chatter can be an issue. if I was a 1-11/2 feet higher I think I would get less chatter.
I'm a big fan of getting my stand way up there whenever I can. Never understood why folks don't generally do that. Less crowd noise, certainly, but also, typically the PA is up there a bit, too. I've found I've had better results than those around me on many occasions, simply due to stand height. YMMV, naturally. It always seemed like a no brainer to me, though.
Less crowd, but not better sound in my experience. The PA might be up in the air, but it is not pointed that way. It is pointed toward the crowd/middle of floor. In a line-array system, if you have your mics up real high, you will be picking up sound that was intended for people way behind you. I have found that the higher you put the stand , the more brittle and unnattural it sounds.
This assumes most venues know how to set up a sound system. Not the case at most venues I record at.
Also, I don't see what' wrong with picking up the sound intended for people behind you? I haven't had the brittle, unnatural sound you talk about here (to my ears, of course), so I'm hoping you/others can expound on that a bit. I guess what I'm trying to do is pick up the sound intended for those behind me, without the crowd noise of those behind me. What's the pitfall there?
But again, the biggest point here is that most venues I'm recording in have haphazard setups of the sound system, and I've found that to be the case almost everywhere I go.