C-D road got busy, even in the early days of TruckersMP (ETS2MP back then) because it's the most central located road of the map, connecting the mainland of Europe (SCS started Europe with just Germany, Netherlands, Belgium, Luxembourg, France, Italy, Austria, Switzerland, Poland, Hungary and U.K) with England... Back when there were also traffic jams at Europoort (Rotterdam) because cargos to the U.K were the best paid jobs. Only veteran drivers will remember.
The road got the reputation of 'death road' because of the chaos it occured (LOTS of traffic jams and trolls), and since everyone is in for a challenge (because let's face it: there's not much of a challenge around the main (base) maps of Europe, making driving a rather tedious experience for some) they would like to take on the challenge themselves. I mean, the most used road in ProMods is also a challenging road (Kirkenes mine trail). I hope that we will have some more challenging experiences in the future DLCs of SCS Software, because we're in for a challenge! I hope it'll be comparable with SCS earlier release of '18 Wheels of Steel: Extreme Trucker'..
My suggestion would be either an off-road challenge, or a tight spot challenge (such as Paris in real life)...