These could be some great add-ons for TSW2 and everyone can travel on the new Aachen-Köln route. 1) The classic German InterCity in his most classic livery (DB BR 101) 2) Historical German loco (DB BR 103) in modern IC version, or like TEE 'Rheingold' service for a sort of revival gala. 3) And why not an ICE competitor? (Thalys PBKA Brussel-Köln via Aachen, here in Köln Hbf)
The classic German intercities sound like a logical thing to do. We have no German intercities yet, and the locos and coaches could be used on many routes. Sounds like a good way to recycle assets in future. The TEE would be nice too, but judging by the amount of historic German content for Train Simulator, it looks like there isn't a whole lot of demand for it. There's a few historic/heritage DLC for Train Simulator, but most of the German DLC is modern. Although the Thalys wouldn't be really typical for German routes, I guess it can be recycled if DTG ever decides to make a French route, or perhaps a Belgian or Dutch route (unlikely to happen, but one can hope).