RE: your question about guards in a more active audience-interaction role:
 
A few years back (or more than a few years back) the Field Museum in
Chicago decided to start a "Visitor Services" department, because some
guards wanted a more active and challenging role.  So they divided the
guards into two groups--Visitor Services and regular guards, and have been
operating successfully, I assume, since then.  The visitor services people
wear red (?) blazers, support information desks, etc., but also wander
around the museum I think.
 
Much of this might be garbled, so I recommend contacting the Field Museum
directly and speaking to whomever is in charge of this department.
Unfortunately, I don't have a specific name, but I do have their number:
312/922-9410.
 
Britt Raphling
Adler Planetarium
(312)322-0510
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