Yes, I can see 2 AC flights. But UA coming isn't realistic. They are AC's partner, and they develop their routes to complement each other. Note that AC doesn't duplicate UA's YYC-DEN flights, among others. UA won't start duplicating AC's. Only on the highest traffic routes do both airlines fly.
Also, realistically we're not talking about a whole lot more airlines coming in. Most new routes will be with AC, no question about it. There is some potential room for other airlines, but not for everybody and their dog to come fly out of here.