A transcendental constraint

I think we should impose something like the following constraint on metaphysics, science, etc.:

1. For each particular member A of the set { ethics, science, external world, other minds, mathematics, the past, ... }, one's views should render objectively unlikely the disjunction of all possible general sceptical hypotheses about A, conditioned on the existence of beings appeared to roughly like human beings generally are (whatever exactly that means—we might not hold fixed the precise content of the appearance, but the manner of the appearance, and the kinds of things that appear).

I don't know exactly what to put in the "..."—I want to leave it open ended. I also don't have a characterization of what counts as a general sceptical hypothesis, but a paradigm example is Descartes' deceiver in regard to all five areas, a brain in a vat hypothesis in regard to science, external world and other minds, the five minute hypothesis in regard to the past, certain evolutionary biological hypotheses in regard to ethics, etc.

This is a pretty strong constraint. I am not merely requiring that no general sceptical hypothesis about one of the privileged areas be likely true. I am requiring that they be objectively unlikely. As far as I know, the only overarching views that satisfy my constraint are theism and optimalism (the view that, necessarily, everything is for the best). Moreover, if Nicholas Rescher is right, optimalism entails the existence of God (it is better that there be a God than that there not be a God).

At present I do not have a good defense of this constraint, other than that it seems intuitively right to me, nor do I have a very good formulation, though there are special cases of it that I can probably put moderately precisely.