Overview:
This is a lighter alternative to BLEED's damage overhaul.
The primary differences here are that explosions and fire damage have not been buffed so wildly, and most body part damage multipliers are not set as high (BLEED had 3x on average).
Bladed weapons cause bleeding when they penetrate DT, which damages health over time, conveys stat debuffs, and repeated hits in a short time can hemmorhage, causing additional stat debuffs and instant health damage.
To complement the bladed bleeding, blunt weapons have been given formula based knockdown.
Ballistic and explosive weapons can also deal a small amount of bleed on crit. (Explosive weapons don't generally crit unless you get a direct hit, but I let it happen in case something reimplements that capacity.) 
And Stay Back and Super Slam's incredibly powerful knockdowns have been redone via formulaic event handler.
Creatures' DT/DR, and fire/energy resist values have been changed as well, to make creatures tougher on average.
Power Armor provides immunity to various scripted knockdown events, like Bighorners and Deathclaw attacks.

Features:
Spread:
There are additional spread penalties while you are in the air, as well as when scoped and moving.

Bladed Bleed:
Bleeding effects occur every time a bladed weapon penetrates DT. The length of bleeding is increased if the hit was a power attack, and the severity is doubled if the weapon is automatic. The hit also conveys a SPECIAL debuff while it is active.
The intended primary way to clear the bleeding effect is Aid Addon's bandages and medkits, though they'll also dissipate over time. There is also a config toggle to allow Stimpaks to stop bleeding for those who don't use Aid Addon.
An imagespace modifier plays when you start bleeding (assuming the imagespace isn't already active) and the player will make a noise, to make the presence of the effect clearer.
The bleeding effect will stack on qualifying hits.
Critical hits that apply bleeding apply extra limb and health DOT.
Repeated hits in a short time can hemmorhage, causing additional stat debuffs and instant health damage.

Crit Bleed:
Ballistic and explosive weapons can also deal a small amount of bleed on crit. (Explosive weapons don't generally crit unless you get a direct hit, but I let it happen in case something reimplements that capacity.) 

Bladed weapons also have a damage debuff vs. robots, and they naturally can't apply bleeding effects to them.

Blunt/Shotgun Knockdown:
Blunt weapons and shotguns have a native knockdown chance when they penetrate DT.

And Stay Back and Super Slam both bypass the need to penetrate DT for shotguns and blunt weapons, respectively.
Super Slam no longer grants knockdown with non-blunt weapons.

Blunt weapons deal an additional 25% power attack damage.

Fire Damage
Fire DOT damage deals 1.5x damage to animals, mutated animals, ghouls, and insects.

Body Part Damage Changes
Most creatures and humans have had their body part damage multipliers changed. Weak points generally take more damage than they did in vanilla, but tough parts often take less damage and longer to cripple. These values are not as high as they were in BLEED.

DT/DR/Resistance Overhaul For Creatures
Creature and robot DT/DR and fire/energy resistances have been buffed across the board. Creatures will be noticeably tougher, and you'll have to use stronger weapons on some creatures that you're not used to taking punishment so effectively. This has been done logically, so that creatures and robots that should be tough don't go down easily, while weaker creatures have just enough of a boost to make them more of a threat, due to their slightly increased tenacity. Robots have generally had their DT upped more than their animal counterparts, as they were often lower than they should have been.
Protectrons have been given a near immunity to fire, to mesh with their lore regarding their design being fire resistant.
Turrets have been made noticeably tougher, but their weapons have been nerfed. Weaker turrets fire more slowly, with more spread, and they fire faster with better spread as their tech level increases.
Feral ghouls deal a small amount of radiation damage on hit. Ghouls which have armor on their models will have some DT and DR.

Geckos have been given some relatively small DT/DR and energy resist, and pretty decent fire resistance. They've also all been provided a small degree of radiation damage on unarmed hit, and the green geckos from HH have been given the same radiation damage instead of radscorpion poison. Golden gecko rad damage has been nerfed considerably.
*This will absolutely affect the balance of Sunny Smiles' tutorial quest. Geckos were pretty tough customers in the classics, and the fact that she hunts them with a varmint rifle can be considered an error in her judgement. Besides, you've done the tutorial quest plenty of times now, just skip it this time and hit those geckos after you've finished the GS gunfight and have a slightly better weapon.
Customization:
Each of the multipliers and values that affect the knockdown chances above are configurable in the New Blood Config.ini.
Stimpaks' ability to clear bleeding can be toggled on in the ini. It's off by default.
Global bladed bleeding effects, hemmorhaging, bladed limb damage, and blunt power attack damage bonus can be toggled in the config ini.

Requirements:
JIP LN, xNVSE, Johnny, the usual stuff.
AnhNVSE is required.

Installation:
Regular installation.
Recommended for use with JIP Localized Damage Fix if you the relevant JIP setting. Highly recommended.
If you aren't seeing the shotgun stat changes, move this mod lower in your load order.

NB should be loaded after any mods which touch Super Slam or And Stay Back, but before S6S Base Game Perks Redux.

Recommended Mods:
This is a part of my "Core" series, which are all designed to work in tandem and balanced for each other:
SWEEP
Sweet Consumables
SPARE
STARS
Aid Addon
New Blood
While these mods will work without each other, the use of all of them provides the intended experience.

Completely/functionally included mods:
Knockdown Perks Nerf
Blunt Weapon Crit Knockdown
Recommended optional companion mods outside of the Core series:
If not using SWEEP/Vanilla SWEEP, Shotgun Buffs is recommended to make sure that shotguns are competitive with semi/full-auto weapons.

Load Order:
Sweet LO
Any of my files not listed here don't have any load order considerations in relation to my other mods.
The listed mods which aren't by me are ones I always have active and need specific LO considerations; if you don't have them, that's fine.

Patches:
Blunt and bladed weapons from other mods will need to be manually patched for this system. I've included a small scriptrunner that you can use to apply these effects to any weapon that you have an editor ID for.

Compatibility:
Laser turret weapon spread and fire rate changes are done by script, to ensure compatibility with EVE.
Automatically handles TTW (3.3+), AGE, DMT, and CFWR.
Aid Addon bandages can clear the bleeding effect.
Patch for TTW + Ragdolls available. NV Ragdolls patch courtesy of <X>.
Compatible with BURN.

Questions:
Is this compatible with BLEED/BLEEDOUT/BLEEDLESS/BLEED Transfusion?
No, it's obviously a replacement/alternative.
Is this compatible with Blunt Weapons Crit Knockdown?
No.
Which difficulty setting should I use?
Normal. This is my philosophy on difficulty settings.

Upcoming Versions:
I may look at creatures' unarmed attacks more in the future.
I may try setting up a visual screen effect to play when you're taking rad damage.

Permissions:
Do whatever.

Support:
If you'd like to support my modding work or say thanks, feel free to donate via the Nexus or here at Ko-Fi.