"Malthusian" is not the simplest explanation. What about Marshallian? It looks like most of these behaviors involve doing something until marginal costs reach marginal benefits. His model involves doing things because they can't be as good as possible without having negative side effects. While this gets you the right result in some cases, it means he needs a separate model for explaining positive externalities ("Why do my neighbors clean their lawns, even though they get a fraction of the total benefit of living in a neighborhood with clean lawns?")
This is certainly an interesting idea, but I'm skeptical. I've noticed that a few practices have that effect (exercise, for example), but it seems to me that it's more a matter of habitually exercising willpower than getting the right mix of experiences. Lots of extremely successful people just spend all their time doing whatever it is that they do well.
For example, when I read this pleasant profile of Richard Posner, I don't imagine that he's a great jurist because he goes to the zoo or plays with his cat; I imagine that he's a great jurist because, aside from playing with his cat, eating, sleeping, and commuting, he spends all his time obsessing over the law.
When I really get depressed I speculate that drug abuse could be the explanation of the Fermi Paradox, the reason we can't find any ET's. If it were possible to change your emotions to anything you wanted, alter modes of thought, radically change your personality, swap your goals as well as your philosophy of life at the drop of a hat it would be very dangerous.
Doubtful. The first person to invent an 'expansionist' drug, that turned users into hyper-competitive, rapidly-reproducing, high-achieving types -- basically, a pill for being a Mormon -- would have lots of offspring, lots of success, etc. Many people choose to abuse heroin, but many people also choose to abuse Adderall, or to use Piracetam or other similar substances. The success-druggies will outbreed and outcompete the orgasm-druggies, leading to more intense success-drugs and perpetuating the cycle.
If you assume that the watchmaker's analogy is true, you will only find machines that either have an obvious creator, or that you assume must have an obvious creator.
But someone who doesn't believe the hypothesis by default can just as easily point to the organelle as evidence. They have evidence. You "assume."