Say I was looking for a community like yours. Since yours is the first one I will likely see much more activity on it and skip the one with 0 if it was created afterwards just for the vanity url.
Since lemmy.ca says it's not restricted to non-Canadian topics and welcomes all, I see nothing wrong if you create it there. Also, if the content isn't images uploaded through Lemmy, I wouldn't worry about taking up resources, as storage space seems to be the limiting resource, not traffic (in the form of bandwidth or CPU time).