"If I give you some green belt land to make a "country park" you let me build houses on another piece of green belt land and make a fortune".
Despite the adjacent by-pass (which would become a through-route, rather than a by-pass) this actually is an unspoiled piece of agricultural land, with ancient field boundaries, streams and ponds. Over the past few years it has become the hunting ground of a group of Buzzards.
A "country park" would suggest a visitor centre, a car park and yet another place where folks with dogs would drive to in their Range Rovers to let the dogs out to relieve themselves.
Please leave the green space between Wilmslow and Alderley as it is. The Wilmslow Vision document says that new housing areas should be sustainable and preferably on brown-field sites. Destruction of what little green-belt we have left is hardly a "sustainable" development.