I'm a bit of a passenger rail fan and someday I hope that Union Station will be the starting point for a train trip on the Canadian to Vancouver or the Chaleur (via Montreal) to the Gaspe Peninsula. As it turns out, the only train that I have taken out of Union Station is the GO Train to Scarborough!
But train-wise, life has still been pretty good. I have taken the Canadian to Vancouver from Edmonton and the Hudson Bay train from Winnipeg to Churchill. The Skeena to Prince Rupert, the Ocean to Halifax, and the White Pass & Yukon from Skagway to the Yukon are also on my future train travel list.
Union Station in Toronto still has its majestic main hall, even though other parts of the station have become a little worn and tired. It and the Royal York across the street are monuments to the old Canadian Pacific and their architecturally impressive stations and hotels.
Union Station is also a major commuting/tourist hub and a neat place to feel that energy. And like many in the crowd, Union Station is a great place to start your day in Toronto. There is so much to see that is very convenient either by foot or by public transit.