(Procreative Reasons Asymmetry): While we have strong reasons against bringing miserable lives into existence, we have no reasons (all else being equal) to bring awesome lives into existence.
I've previously argued that considerations of demandingness suffice to explain why people are not generally obliged to procreate, in a way that leaves untouched the commonsense idea that awesome lives are amongst the best things the universe can contain, and so (all else equal) it's generally a good thing to bring about more such awesome lives.
We may now add: Since we have (some) reason to bring about good outcomes, we thus have (some) reason to bring awesome lives into existence. So PRA is false.
To illustrate with a simple case:
(Distant Realm): Suppose you learn that a new colony of awesome, happy, flourishing people will pop into existence in some distant, causally-isolated realm, unless you pluck and eat a particular apple. What should you do?
The apple looks pretty appealing, let's suppose, so all else equal you would be inclined to eat it. But in this case, it seems to me, you shouldn't. Preventing those good lives from coming into existence would be a real shame, so there's a real reason not to do it -- indeed you've surely got stronger reason to refrain from doing that than you do to enjoy a mere apple. It seems to me positively wrong to choose the apple in this case.
This case then brings out that (contrary to, er, just about everyone currently working on this topic) there isn't even any fundamental deontic procreative asymmetry. All else equal, it's wrong to prevent good lives from coming into existence, just as it's wrong to bring bad lives into existence. In everyday circumstances, we're not obliged to procreate because not all else is equal -- it would be hugely demanding, most obviously for the gestating woman, but I think there's also some plausibility to the idea that people have a moral prerogative, not easily overridden, over their genetic material, which makes it difficult for morality to demand that they create a biological child. But these reasons are specific to human biological procreation; they do not advert to bringing people into existence in general (which would include bringing unrelated people fully-formed into a distant existence where they won't impact upon the agent's life at all).
I conclude that the widespread belief in a fundamental procreative asymmetry is a result of people's failure to recognize these contingent (even if perhaps humanly universal) confounding factors. Even the abstract form of the standard case introduces confounders, by contrasting a putative negative duty (do anything but this: procreate [given that the kid would turn out miserable]) with a putative positive one (do precisely this: procreate [given that the kid would turn out happy]). This is not the way to test for a fundamental normative asymmetry between good and bad possible lives.
By contrast, when we control for confounders by considering a simple case like Distant Realm, there no longer seems to be any fundamental asymmetry. (Do your intuitions agree?) You're not obliged to procreate, but that's because your claims and interests matter, not because the possible future person's interests don't.