It should be a seamless experience, except some books that you may want to have bought in the UK may not be available in Canada. Books that you have already bought are yours forever regardless of where you bought them.
On Kobo, the service first checks your billing address country if you are logged in. If you are not logged in or do not have a billing address country, it checks your IP and resolves that to a country. The content is then restricted based on which country the service "thinks" you're in.
So if you have a canadian credit card with a canadian billing address, you'll be viewing Canadian-rights content even if you're logging in from the UK.
For your last point a couple of things:
1. As long as you can download a book in a supported format (proxy or not), you can add it to your Kobo Touch.
2. Kobo Touch supports Adobe DRM, which many independent online booksellers use for their DRM. As such you would probably find no need to strip the DRM.
Hope that helps,