In my other post I put forward the argument that you can't coherently say which world is preferable, at least in cases when the alternative metrics disagree. So I have therefore not made any such statements myself.

I think what you propose is a rational view which lacking an alternative I would espouse. This seems regardless to really just be a justification for average utilitarianism, at least if we consider the expected value of utility in a population when evaluating its worth. That faces us with what are often considered oddities of average utilitarianism, such as:

For instance, the principle implies that for any population consisting of very good lives there is a better population consisting of just one person leading a life at a slightly higher level of well-being (Parfit 1984 chapter 19). More dramatically, the principle also implies that for a population consisting of just one person leading a life at a very negative level of well-being, e.g., a life of constant torture, there is another population which is better even though it contains millions of lives at just a slightly less negative level of well-being (Parfit 1984).

To be honest I generally prefer the prescriptions given by average utilitarianism (opposed to total) but I'd lke a theory with fewer seeming paradoxes.

(In the first case considered by Parfit, DC suggests staying in whichever population you are in. In the second, it suggests both populations strive towards the single person population.)