As a rule, when there is a need to go on a business trip, you can easily do with hand luggage. Only in any ordinary small suitcase that you definitely have in stock, your suit will not remain untouched by time. The most perfect way to do that is a garment bag, I think. Initially, this was the name of a travel bag for bedding, but nowadays, the portlet has been re-qualified as a garment bag for suits. Does anyone use it?
There is a wonderful city of Antwerp in Belgium, the birthplace of Rubens. The city is located on the bank of the Scheldt River. It has many attractions, there is something to see and admire. It is not difficult to get there from Brussels, but it will also be convenient to combine Antwerp with a visiting Rotterdam (if you are traveling in the Netherlands), or you can drive out of Germany for a day (Düsseldorf or Cologne)... you can take a car in Antwerpen and see everything in a few hours.