I'd like to second having Arcanis visit the Calgary Comic and Entertainment Expo (CCEE). (
http://www.calgaryexpo.com/) (Occurs mid-late April)
Like Nierite said, there is a good size group of us here in Calgary that play Arcanis, and almost everyone who plays Arcanis also goes to that Convention. I haven't gone to any RPG gaming at CCEE, so I'm not sure how much there is, but if Arcanis does come to this convention you would definitely get us locals showing up for the event.
Plus I like to think that Calgary is a good mid-point for western Canada, and from my understanding is one of the larger conventions in western Canada, so lots of people from other places could attend and/or will be there.
Also I should mention, over the past couple years there has been talk within the Calgary group of having our own mini-Arcanis convention so that we could justify getting the BIs here. lol There is definitely interest.
Another Canadian option could be Fan Expo in Toronto. (Occurs late August) I've been to that convention a few times. From what I've heard it's the biggest in Canada, and has a good RPG gaming area. Arcanis could fit in there as well, but I don't know how many people in Ontario play Arcanis, and I'm not sure how many people from the active Calgary group would be able to go to Fan Expo. So I'm unsure of what the turnout would be.
That's my two cents.