Maybe the only way to mitigate the risk of the capricious app store gatekeepers is to build enough relationships with Apple to bypass them (like ngmoco seems to do). Maybe that requires being a big(ger) company.
In short, if you are reasonable (e.g. not trying to sneak in a porn app or an app that obviously violates Apple's terms) you are practically guaranteed that you'll get your app in the store. And if you are not reasonable being big or close to Apple will likely not help you much.
(By the way, I cannot come up with a single case in which ngmoco might seem to have bypassed the approval process. Do they have a tits app in the store or something?)
He was flat out rejected. After being suggested to put in-app purchasing in his app.
I'd say "App store reviewers are tired, cranky, varied from one another, pissed off when people dump crap on them, and unwilling to go out on a limb when in doubt", and that accounts for 90% of all the rejections and behavior we see from them.
Either way, they're not liable in the slightest for it.
All of that aside, it doesn't really matter. If you don't want to get into a call recording app, you say that at the beginning when first shown a call recording app. After you've suggested a company do 10k worth of development, then make a policy rejection on something the app has done since day one, you've screwed up.
You can make immersive beautiful apps. But you have to go about it the right way.
Apple only approves working code. This means you have to get iterative in the correct way to 1> Lessen your chance of late rejection and 2> Ensure you have approval the entire way.
If you're making an app, make a simple version of it first. Submit it for approval, after approval or rejection, fix those problems it has, then resubmit. Iterate this. Only when you've got a pretty much done project, buy the art, add it in, then resubmit.
There are apple development liaisons who you can develop a relationship with, but honestly, they'll call you even if you don't have one when they think your app is in the "sweet spot" of "rejected by approvable with just a little tweak". The relationship is pretty much only useful to "get" their mindset faster, it doesn't really get more things approved.
Is there a risk they'll end up rejecting you wholesale? Yup. But it's pretty reasonable to get a feel for what areas are verboten, and which areas are largely in the clear. Stay in the latter, and you're usually far far from fearing rejection.