First point: none of those are objectively good things, and, at the very least, depend on an individual group's goals.
Fair enough. I'll note it as a point of probable contention, unless you specifically discuss this with your players before the game.
Second point: The average on-screen lifespan of the vast majority of creatures the party encounters is something like 1-5 combat rounds. That is the entire duration that their statistics and capabilities are on display and relevant. That is not enough time to get much of a sense of anything aside from a relative measure of "easy to kill" and "will kill us easily." Even if you create an NPC using precisely the same rules, if the players never see that NPC take a short rest or gain a level or whatever, it's not relevant to the play experience.
Exactly. This is the major selling point of using fast stats rather than writing everything up long-form. It's also why the players need to be able to trust the DM, since they won't have enough time (or reason) to deduce the actual stats of any given NPC.
Third point: It is not necessary to use equivalent mechanics for NPC's to give players a sense of their characters' place in the world.
It certainly helps, though. Not to drag out the edition fodder, but it's really hard to tell where a 4E character fits into a world full of minions and elites and solo monsters. If NPCs are
literally incomparable to PCs, then it's difficult to get a sense of what it means to have Strength 18 or 45 Hit Points or anything.
It can be used both ways, y'know. That little chart defines what the CR for a given value of offense and defense is. You can start with the CR and then determine a relevant offense and defense just as easily as you can start with an offense and defense and figure out what it's CR would be.
I'll look into this when I get a chance. That doesn't describe my understanding of how the game is supposed to work, but it's certainly worth looking into.
I wouldn't go assuming that class mechanics are necessarily universal. A super-powerful-wizard-with-almost-no-hit-points perfectly describes, say, the young child whose soul is entwined with the half-resurrected spirit of a powerfully evil archmage who is using the little girl as a mobile pawn to gather the remaining bits of their shattered soul to eventually rise to true prominence.
That is precisely the kind of thing that would really get the players to questioning, though. If you shoot the girl, and she dies from the first arrow, then you
know that there's something weird happening because
that doesn't fit into their understanding of how the world works. And in this case, there
is something weird going on - the girl was pseudo-possessed by an evil wizard.
And the reason they know that something weird and exceptional is happening is
because powerful wizards always have a ton of Hit Points.
