@Samantha: Thanks for the link, I quite agree with many of his thoughts. I don't know that I'd go so far as to say "tear it all down," but we have to realize that much of what we consider the norm is a relatively recent invention. Finding balance is something I think is the key (as is so often the case).
@PSMKay: As for precautions, I'd say having good instructions for front-of-house staff and ushers is important. Sometimes we work in theatres that have that, sometimes we don't. In my earliest community days we often performed in a music school, setting up thurst staging in the largest room with chairs on risers. It was very, very intimate. We often stationed an usher on the "stage" just to help direct audience members to the correct "aisle" and keep them from touching set pieces.
I like the suggestion you made of putting things out for audience members to do. Often intermission is purely about waiting for everyone to get back from the bathroom, so that those who left are simply waiting around. Perhaps instead of just ads and bios, the program could have something interactive in it (depending on the show, of course)? Like: see how many things you can spot in the theatre, with explanations of what they are? I don't know, if you've got a website or mobile app at the theatre, it could be truly interactive as well. Something for the noobs to learn and that the vets can ignore if they like.