If I may say so, I don't think you want accountability in relation to the work of that kind of body. You want the government, represented by the PM and his colleagues on the front benches, accounting to you for what they've done, either against the promises they have made or the obligations that are in the law. So you need the right set of obligations in the law and you need to prompt them to make the right sorts of promises; then I would say you would hold them to account for that.
I actually don't think it's useful or productive for Parliament to say, here's how we want you to run your kitchen, and we're going to hold you to account for having run the kitchen in this precise way or that. You want to look at what's coming out of the kitchen. What are you getting by way of policy and program commitments, spending, and fundamental changes?