Can we get an entry for "Production Manager" in the Project > Properties window?
+1
Another way to solve this problem would be to allow the job titles to be edited while retaining the variables' functionality, so instead of/in addition to $(Director) it could be referenced by $(JobRole1) or something.
I will never have all 5 of those fields filled (most of the time it's my name for all) but I will have 5 relevant contacts which currently end up in notes, or the accompanying emails.