Not as significant as a complete structural reform of the Church of England, which is what you are advocating.
I don't see why it would be a major structural reform, let alone a complete structural reform, given that the current structure of the CofE involves parishes that are overseen and responsible to the diocese. If parishes were somehow completely independent then why do they have to report to the diocese and why does the diocese have a level of governance and procedural control over the parishes. Realistically the parishes are just a local branch of a larger organisation.
But right now the inefficiency and poor governance is not the responsibility of the Church of England, it's the responsibility of each individual parish.
Not really, as the parishes report to and are responsible to the diocese.
Why would the central part of the Church of England want to take that on?
Firstly because it already does, given that CofE accounts are collated from diocese and parish. But at the moment any dirty washing is hidden - so if a parish is a basket case the only people who really know are the higher level organisational structures of the CofE.
If on the other hand tens of thousands of parishes are reporting directly to the commission and a proportion of those (even a small proportion) are non compliant under the regulation it will be the CofE who gets it in the neck. The media won't separate out the parishes from the overall CofE, because most people don't know, nor care how the CofE operates itself. The 'news' headline would be:
'CofE fails to meet charity requirements' - with the news item reporting that 100s of CofE churches are failing to meet the commission regulatory requirements (and that might be just 1% of those charities)
So it will rebound on the CofE, so surely the CofE will want oversight, and the way to get that is for parishes to report upward in the CofE and the more centralised structure of the CofE to ensure that everything is OK before submitting to the commission.