There were long negotiations about the sharing of time to reflect the relative strength of the parties in the House of Commons rather than individuals. As I've argued before, as the Conservatives and the Liberals have five-minute rounds, they can split those rounds so that all their members get a chance to participate. It's really up to the parties, if they wish, to make that decision.
If we're going to change that, we would need to then renegotiate the number of minutes, because, with respect to Mr. Bezan's proposal, it means that there would never be a second question from the Bloc and the NDP, for any practical purposes.