Whatever you choose it will most likely not be your first or last vehicle so why not start with something cheap to figure out what you really need based on real life experience. I see people in plain old trailers camping in ski resorts and people in stock Subarus driving jeep trails so a full blown 4x4 expedition rig might check a lot of boxes you don't need.
I'm a big fan of EC (more than ER) but the lack of a garage area for bikes and skis does not work for me. I've had my bikes on a hitch rack before and did not like the extra maintenance that it caused. Having them on the bed of the truck under the cap was a big improvement and having them in my van now is great.
The one setup I keep coming back to when I think about full timing is a class C with rear corner bed. They usually have a huge storage space underneath, sometimes enough to put 2 bikes. You keep that for gear that can handle the cold and you put your bikes inside on the bed platform. You can move the fresh water tank inside and all the piping quite easily and use the bed over the cab for sleeping while still having a dinette to sit and rest. Add 10k for a 4x4 conversion and you got yourself a pretty nice rig for less than $100k or even less than $70k if you buy a 2 year old unit. And even better you can get something that is 22-24 feet long, easy to park and drive in the city. A Tiger RV is also a nice option.
Fraser way in Canada has its own fleet or Class C rentals for Canadian weather. One of the option is the
Overlander which is 4x4. They sell their rentals after some time and you can find them online.
Or if you want the look you can get a
Predator II with washer/dryer, extra insulation and any other customization you want. Brand new will be half the price of an ER and as with a class C you use the bunk area as a garage.
You can also rent an ER or a Tiger for a few days/weeks and see how you like them.