You should indeed visit the Eifel. It is a awesome place. And for me, as a stuborn Southern Dutch dude, I never seen the northern part of holland (only the training grounds)
You've missed the best part! The Frisian lakes and Wadden Islands are beautiful! Although especially during the summer i.e. when the sun is shining.
To be fair, as a true blondhaired, tall, calvinistic protestant from north of the rivers I've never had a holiday in Limbabwe. Only drive through on my way to France.
Eifel and Mosel area are indeed beautiful! But so is the Röhn area and lots of others in Germany. I like Germany. Beer is good and cheap!