I take the Crescent overnight every now and then. I usually stay holed up in my room and try to read a book, but just watching the scenery is enjoyable and takes up a lot of attention.
The Superliner trains such as the Sunset Limited are much better since they have lounge cars with seats facing nearly wraparound windows.
I think a long train trip with a spouse would be fun, but I'd take the Coast Starlight to Seattle instead. The scenery (particularly towards Seattle) is beautiful and the lounge car might be better (Google "Pacific Parlour Car").