Jakuma, if I can be helpful...
I can read Dutch and did parts of this tour the past five years, anyway made tthe leg Oudenaarde (Belgium), Brussels, Leuven, Maasticht (Netherlands), Aachen, Trier, Koblenz last year.
But why that focus on Trier? I had that same 'dream' (oldest German town) but towns as Aachen and small jewels in the Eifel give more variety and a splendid scenery!!!
Go from Aachen through the Eifel (Bad Muenstereifel, Altenahr, Bad Neuenahr and Andernach) to Koblenz etc.
Did you know that Charlemagne (Charles the Great?) was analpabetical. All this you'll find out in Aachen (if you can read...German).

From northwest France to northeast France is rather dull, an industrial area and then a large agricultural area with monoculture (grain), so going to Belgium is more interesting.
Any questions? Tell me.