From the CLG highlights, I think that for this to work:
"Giving communities a greater say over their local planning system"
we will need this:
"a comprehensive review of local government finance"
or something similar to provide sufficient incentives to make sure that new commercial and residential building can happen in popular places where people and firms want to locate.
Devolving decisions coupled with a system that provides decent incentives should be a better solution than top down spatial plans. But the first without the second will spell trouble in the form of restricted supply leading to higher (and more volatile) house prices and commercial rents.