In their award winning book, Peter Aucoin and his colleagues write (p. 183):
“When a government loses confidence, there is no logical reason to dissolve the entire House since, in this circumstance, we do not need a new House of Commons; rather, we need a new government. Parliamentary systems allow elected representatives to choose a new government on their own when they no longer have confidence in the incumbent. The principle is that neither the prime minister nor the governor general should decide: the House must decide.”
These comments were mainly directed at minority government situations in Canada, although theoretically it would also apply to majority government situations if for some reason the opposition parties and a large portion of MPs in the governing party voted against the government in a non-confidence motion.
On the one hand, I find this logic compelling, given that Parliament is supposed to be sovereign in Westminster parliamentary systems. As well, as Janet Ajzenstat convincingly argues, it truly is the only institution in Canada that can legitimately speak on behalf of all Canadians. On the other hand, the logical extension of this argument is, why bother with elections at all, at least until every party in the House has had a chance to form the government and be defeated on a confidence motion?
I think the solution is some sort of middle ground approach, in which only the official opposition party, either alone or as the leader of a coalition, has the opportunity to form a new government after a non-confidence vote passes. Once this new government is defeated, only then could a general election be called.