The 'more effective' bit is lost on me. I read through the full post (ok, I admit, I just read the posts containing 'sneak') and I see you are putting a lot of work into modifying sneaking. But there seems to be a shortage of details. Yes, sneaking is very un-realistic in some ways, but reading your descriptions leaves me picturing a soft foam ball. As a sneaker I'm already SOL if I get detected. So what's in it for me, aside from an advantage with the occasional dozing raider? Here are some observations from my skulking about, with relevant questions:
My mod makes sneaking more strategic. If you are careful, you can remain undetected at distances that are much closer than with the default settings.
In the default game, with all else being equal, you are detected indoors when you are ~117 ft away; and outside, when you are ~234 ft away.
With my mod, you can sneak closer (if you are careful): indoors you can get within ~84 feet, and outside you can get within ~194 ft.
The "careful" part involves wearing light armor [quieter under 10 lbs (than default), but noisier over 10 lbs], staying in the shadows, not turing on you PipBoy light, not moving when NPCs are looking in your direction, not running, and not firing off your gun.
In the default game, you can shoot an NPC while undetected and another NPC who is standing right beside the one you shot will not even react. With my mod, the second NPC with know right where you are (from your gun shot), and come after you.
When being heard rather than seen is the issue, will I be better or worse off? Because from point 5, it seems like worse off. Already I get detected absurdly early when coming from behind, even at night. And what about during the day or in more intense light? If I am unseen, does the light level still affect things?
My mod makes sneaking a bit more realistic. Being stealthy involves being quiet, so unless you are being stealthy, you will be worse off with my mod ... in the sense that you'll have to work harder to sneak up on someone. But the plus side, as I detailed above, is that you can also sneak much closer if you are careful. You can get closer at night, than in the daylight, but there doesn't seem to be any real difference between sneaking on a sunny day or on an overcast day. Inside the difference in lighting has a much greater effect ... so stay in the shadows. And my mod increases your chance of re-hiding after you are detected.
Will my critical sneak head shots with a 10mm continue to be lethal (to humans and lesser beasties at least) at higher levels, unlike vanilla? And when not lethal, can you expound on the effects of head crippling? It doesn't seem to have any effect in vanilla.
My Sneak module does not touch weapon damage.
My Survival module affects weapons and armor, but there is no easy answer to your critical head shot question, as there are just too many factors to consider.
I reduced the Combat Sneak Bonus for both guns and melee (in my Survival module), but with my mod ALL weapons now do 2.5 times more damage (but will not do nearly as much damage if they are not in good condition); and everyone (including creatures) have considerably less HPs; but All armor has 50% more DR (but much less DR when not in good condition). If your weapon is in good condition, and your arms are not crippled, and you have some decent skill with small guns (like 25 or higher) you should find that it takes fewer shot to kill both NPCs and creatures. Of course your character will also be easier to kill. So this works both ways.
Perception is reduced a lot more when you are suffering from a concussion (when your head is crippled), so enemies will be harder to spot and you won't be able to aim nearly as well.
I see you take away the warnings, but I figure the game effect is still there. One thing that I'd love to see is the sneak attack multiplier to extend into 'Caution' mode. That alone would be worth the nerfs. Without it, though, it seems this would make a sneaker unplayable.
I just removed the text warnings ... the effects are still all there. As I explained above, I reduced the Combat Sneak Bonus. It was too high in my opinion: a bullet doesn't do more damage just because the victim doesn't see their attacker (I did not remove the bonus, due to gameplay ... but I reduced it quite a bit).
As I've pointed out, my mod makes sneaking more strategic. With my mod a stealth character is VERY playable (but a stealth character does not wear heavy armor, try to hide in brightly lit areas, turn on their PipBoy light, moving when NPCs are looking in their direction, run when NPCs are nearby, or fire off their gun, and not expect to be noticed).