I've only ever flown to Europe and home. Once there, among my most enjoyable aspects of the journey is the travel by train and ferry. I want to actually see the places I'm visiting and I've always loved to watch the world go by out the window, and I'm not in a big hurry. One of the most beautiful sunrises I've ever seen was at breakfast on the North Sea taking the overnight ferry to the Netherlands. One of my best nights of sleep was to the rhythmic clickety clacking and rocking of the train and rails from Edinburgh to London on the Caledonian Sleeper.
As far as hiccups or minor issues --
...I was eager to experience the sleeper train’s cozy elegance...
I think it's a matter of reasonably moderating one's expectations. It's easy to embrace the romanticism of such journeys and methods of travel -- I certainly do. But do temper expectations. Cabins are going to be small and the deluxe toilet/showers confined. Beds are not going to be the most comfortable and the pillows and towels will be thin.
While the cabin was as clean and cozy as I expected, in some areas, Nightjet fell short. The pillow was thin and small, and much to my kids’ chagrin, there was no Wi-Fi. The only “towels” provided were the washcloths from our amenity kits...
See, I do not consider this a matter of NightJet falling short. I think to myself "well yeah, okay it's a train".