Thanks for the advice everyone - it was a *wonderful* trip. Beyond my expectations. Made good friends and had a good time. Was kind of disappointed by the Trench - been through the high parts of Smoky Mountains many times (It's a must-do - amazing to see Ashville, NC from up on the mountain highway), seen that kind of scenery alot (guilty to say I watched a movie in the Skyline for a good bit of the Trench after Pyramid Falls). First half of the Rockies and Vancouver, along with the rest of the trip, were AMAZING. The Trench was too, just kind of repetitive for me.
Planning to go back this winter! I'm curious, however, when's the best time to go in winter? I was thinking around Christmas, but I'm interested in a time when it's decently busy so I'm not alone on the train.