Just returned from Brussels a few weeks ago.
Our DL MD-11 from ATL had a real gate, but it was a Sabena gate/Sabena codeshare flight. Six days after that flight, DL/SN officially went splitsville, so DL probably doesn't have a real gate anymore.
Customs was a breeze, baggage claim took forever (BizElite bags came out right away, but the TPA agent didn't have any priority tags

).
I highly recommend you get some
Neuhaus chocolates. We got a box (you can pick out your own or get a pre-picked one) and are still enjoying them today. They are served on DL BizElite FWIW.
Food was excellent. Between Brussels and Brugges, I don't remember have such good food in a long time! Well, London rivals it.
Why can't Tampa have any world-class restaurants!