A successful religion must serve Moloch, and your designer choice is how much and what exactly are you going to sacrifice first.
Not a bad first approximation, however, let's examine Gnon, or Moloch if you insist on that terminology, a little bit first. Notice that of the four of Gnon's sub-processes all but Cthulhu naturally, if in some cases rather brutally, converge towards making people believe true things or at least having an accurate working model of local reality.
Cthulhu is different, it causes people to engage in signalling completions that may very well result in them competing to believe ever more false things. In a way this signals "I'm so high status I don't need to have an accurate model of what the peasants are doing". One thing religion can do, when it's working right, is keeping a throttle on this kind of status competition, by accusing anyone who starts saying anything too outlandish of heresy. Of course, there are several ways this can go wrong. For example:
1) some outlandish thing may turn out to be true.
2) once it ceases to be conservative (as is happening with the quasi-religion of "social justice") it starts accusing anyone saying insufficiently outlandish gets accused of heresy.
This topic is vague and open-ended. I'm leaving it that way deliberately. Perhaps some interesting, better defined topics will grow out of it. Or perhaps it's too far afield from the concept of less wrong cognition to be of interest here. So I view this topic as exploratory rather than as an attempt to solve a specific problem.
What useful purposes does religion serve? Are any of these purposes non-supernaturalistic in nature? What is success for a religion and what elements of a religion tend to cause it to become successful? How would you design a "rational religion", if such an entity is possible? How and why would a religion with that design become successful and serve a useful purpose? What are the relationships between aspects of a religion, and outcomes involving that religion? For example, Catholicism discourages birth control. Lack of birth control encourages higher birthrates among Catholics. This encourages there to be a larger number of Catholics in the next generation than would otherwise be the case, Surely there are other relationships like this? How do aspects of religion cause them to evolve differently over time?