Yeah, I've used the full dress uniform for diplomatic meetings as well, and generally swap between the other two uniform options for Citadel visits.
Edited to add:
My FemShep can't really complain about Vega's comments, because she started it by saying "maybe I'm here for the view" during their first real conversation on the Normandy
while Vega was exercising.
Damn, I had forgotten how scary a renegade Shep can look. My FemShep just hit the scary glowy eyes point.