I looked into PEI also, not sure yet. But Halifax downtown is good area and close to many things. I know you can get from Calgary downtown to Banff via public transit. As I do not drive I do my research about getting around everywhere with transit.
Sleeping on a moving train I think is great, it is just like being rocked to sleep. As it is I get sleepy just being in a car moving after an hour or so 
I rather do without a tour group, explore more freely and experience the places more in my own time at my own pace. I watch many videos and street views during my research so that when I reach my destinations I am not at a loss. I have many printouts and screen shots downloaded .
When I go to Calgary the bus from the airport to my hotel (drops me one traffic light from my hotel) and in Vancouver, the skytrain station that I will be coming off from is right in front of my hotel. And the Via Rail station in Vancouver is a few stations away.