I would think Ontario is the centre of Canada as it has the most people and the financial centre. Google's AI says 38% of GDP. And the problem Alberta faces is who wants to separate, what do they want to do afterwards and what ground do they actually own (vs. treaties that predate Alberta).

When Alberta at least catches up to Quebec in practicing being independent (runs its own police, collects its own taxes, has its own pension system, maintains foreign services, ... They might decide the extra taxes to pay for such is less "fun". And they need a border to ship stuff through.