Having just spent about 15 minutes in line at the downtown post office, I have three suggestions for the USPS. Since this location probably isn't going to be sold anytime soon due to its clear historic value and designation, not to mention its central location and the on-going parking hubbub that would preclude any overstuffed project for awhile, how about giving the lobby a coat of paint?
The yellowing scotch tape bits, the holes and hangers from signage that is no longer there and the general grime of daily use could be fixed up in a couple of days by any commercial painter. Next, since the acoustics are so good in the lobby how about a little music? As the wait grew interminable and no one was talking, including on their cell phones, the buzz of the florescent lights was palpable. Even something completely harmless like KOIT on a portable radio would be an improvement! Think retail therapy to go along with the Valentine's Day card display!
Lastly, having only one window open should be a rare event. I have no idea what the guy in the leather hat's postal business was, but it must have been complicated to take so long. One doesn't need to be an expert in queuing theory to figure out the impact of a single window especially on Saturday mornings.