Seeing how Canada has become expensive, and numerous restrictions, I probably shall not repeat my trip back in 1989. As a young man of very limited means, I did it on the cheap. I found coach seating very comfortable, but spent occasional nights in youth hostels at C$10 a night in the dorm with very good company, or YMCA.
Itinerary was Toronto via Thunder Bay to Winnipeg, 'day off', then to Churchill and back to Winnipeg (old F units still), then Canadian Pacific route to Lake Louise, day off to take the classic photo at Morant's Curve, then to Vancouver. Back via Jasper to Winnipeg, then via Hornepayne to Sudbury (F units again), overnight stop, then to Montreal, overnight stop, then Quebec City and back, finally overnight train to Toronto. This was all done on a railrover type ticket for C$120 (reduced from C$180 for Youth Hostel Association members!). Unlimited access to the dining car, where dinner was C$6 as I recall. A superb travel agent in my home town sorted out all the reservations for the trip, with no extra charge, and I had no problems with late running trains. The seating was comfortable, and happy hours were spent in the observation dome without any time limits, and I met a lot of like minded people, although not as fanatical about rail travel. My trip had been prompted by learning of drastic cuts to Via Rail coming up. Having the previous year travelled over the Newfoundland Railway (Bishop Fall to Corner Brook), and then from Sydney to Truro and then through Maine (USA) to Montreal, I can lay a reasonable claim to having travelled by train from one end of Canada to the other.
My wife would not go for such basic conditions as I did then, but in 2009 we flew to Vancouver for a non rail holiday, but I was allowed a return trip over the Vancouver Island Railway (Victoria to Courtenay), which we both enjoyed. Sadly this line appears to be closed permanently, although I believe there is a local movement to restore service.