How To Stop Brush From Growing On Raw Land

I bought some land two years ago to build on. Land was/is raw and is about 3-4 acres in size. Had all the pines clear cut and stumps ground down. Once all the trees and stumps were gone I had the land mulched. I sprayed 24D in an attempt to keep the brush and weeds at bay. Blackberry briars took over the land. So this summer I bush hogged everything and sprayed with grazon next which has a done a good job of keeping the briars killed off.

My brother-in-law says I need to plant Ryegrass this winter to choke the briars and weeds out. That way I'll be able to start fresh next spring with grass. Thoughts on this? I don't necessarily have to have a field of lush grass. I'd be fine with grassy weeds, somewhere the kids can run around and play. But I'm afraid if don't do something then I'll be back where I was last year fighting the briars and brush. What's the best course of action?