Well if you keep the curtain on the doors open, then you'll still be able to look out the window across the hall. And if you see anything really interesting, you can always step out into the hall to look out those windows.

It's really only the roomettes that don't have a view out of both sides of the train, especially if your neighbor closes their curtain something that you can't control.

And then yes, there is always the lounge.

Besides, by the time you spend some time in the lounge for the departure snacks, eat dinner in the diner, you won't have that much more time left for seeing things anyhow before it's dark.