You have already got some good responses. My issue would be the lack of campgrounds and dump stations. The weather has been nuts this year, +12C one day and -35C the next. Around us (southern Alberta) we have had a lot of snow and it has stayed longer than usual. Add to that around our neck of the woods the winds this time of year.
Myself if I was doing the drive up north to look at lights and then back without staying or stopping a lot on the way I would probably take a smaller vehicle with better gas mileage and hotel it. Not that it would not be fun with the TCer but you are looking at a lot of issues to resolve and a lot lower MPG without a lot of benefits for a quick trip.
The nice thing with the TCer is that if you do get up north and the lights don't show you can stay for a lot longer with less expense than if you were staying in a hotel. The other is having a 4x4 you can be a lot more relaxed when driving should the weather turn and you have to drive in some deep snow.
If you are looking at going into BC you will need snow tires or chains. Without them you are looking at a ticket and issues should you have an accident.
If you decide not to go that far north my brother has a golf course that has cabins and a RV lot in Northern Saskatchewan and they get a lot of Northern Lights around their place. They are outside of the big cities and the nights are really clear there. This time of year RV park is closed but I am sure he would find a place for you as would many other places that are in an off season. Again the issue would be dump stations.
If you are planning on taking your time and want to take the TCer there are a LOT of amazing places to visit in the winter if you take your time and drive for the weather - Yellowstone, Waterton, Banff, Ice Field Parkway, Athabasca Falls, Jasper, Elk Island National Park and more. Just be prepared for the weather and you will love the lack of tourists.