Make Monsters Scary Again! (MMSA)
Description:
Have you ever thought Minecraft was getting too easy? Do you wish that the monsters were threatening like they once were when you started playing? The Make Monsters Scary Again (MMSA) Addon does exactly what it says it does: making the Minecraft monsters scary again. This addon adds no new mobs or features, instead it tweaks the stats of the vallina mobs to make them threatening once again.
Currently, only the monsters pictured below have been changed, but more monsters and other changes will be added in the future!

Video:
The Changes:
General Changes -
>Increased targeting distance
>Monsters now target players through blocks (they no longer need to see the player to target them)
Basic mobs:
These mobs are balanced around the player having iron and unenchanted diamond tools. By the time you get enchanted diamond tools, these mobs should pose little threat.
Zombie -
Standard Stats:
>Health: 30
>Movement: [0.20-0.35]
>Attack Damage: [1-20]
>Time to convert to a drowned: 3 seconds
Baby Zombie (viarent):
>Movement: [0.40-0.50]
>Attack Damage: [1-3]
>Scale: 0.5x
>Spawn Chance: 4%
Giant Zombie (varient):
>Health: 60
>Movement: [0.40-0.50]
>Attack Damage: [1-3]
>Scale: 2x
>Spawn Chance: 1%
Skeleton -
Standard Stats:
>Health: 20
>Movement: 0.3
>Fire Rate: [0.25-0.75]
Slowness Skeleton (Variant):
>Shoots slowness IV (0:02) arrows
>Spawn Chance: 25%
Weakness Skeleton (Variant):
>Shoots weakness I (0:30) arrows
>Spawn Chance: 25%
Poison Skeleton (Variant):
>Shoots poison I (0:15) arrows
>Spawn Chance: 25%
Creeper -
Standard Stats:
>Health: 15
>Movement: 0.2
>Detonation Range (how close they get before exploding): 0.75 blocks
>Fuse length: 0.5 seconds
Spider -
Standard Stats:
>Health: 16
>Movement: [0.45-0.55]
>Attack Damage: [1-3]
Baby Spider (Variant):
>Health: 5
>Movement: [0.55-0.65]
>Attack Damage: [1-2]
>Scale: 0.3x
>Spawn Chance: 20%
Giant Spider (Variant):
>Health: 25
>Movement: [0.35-0.55]
>Attack Damage: [6-10]
>Scale: 2x
>Spawn Chance: 3%
Drowned -
Standard Stats:
>Health: 20
>Movement: [0.20-0.25]
>Underwater Movement: [0.25-0.45]
>Attack Damage: [4-10]
Baby Drowned (Variant):
>Movement: [0.20-0.25]
>Underwater Movement: [0.45-0.55]
>Scale: 0.5x
>Spawn Chance: 5%
Enderman -
Standard Stats:
>Health: 40
>Movement: 0.8
>Attack Damage: [10-15]
Nether mobs:
These mobs are balanced around the player having enchanted diamond tools. The Nether is a very dangerous place, and so you should make sure to bring as much food, milk, and arrows as possible.
Wither Skeleton:
Standard Stats:
>Health: 40
>Movement: [0.2-0.35]
>Attack Damage: [15-35]
>Withering effect duration: 30 seconds
>Detection Range: 4 blocks
>Will NOT attack you if you’re wearing a mob head (unless you attack them, of course)
>Can Spawn with helmets and higher damage swords
Blindness Skeleton (Variant):
>Attack Damage: [5-15]
>Gives Blindness effect instead of Withering
>Spawn Chance: 50%
Blaze:
Standard Stats:
>Health: 10
>Movement: [0.33-0.53]
>Attack Damage: [15-25]
>Ranged attack burst shots: 8
Ghast:
Standard Stats:
>Health: 10
>Movement: 0.03
Baby Ghast (Variant):
>Health: 5
>Movement:[0.10-0.15]
>Scale: 0.5x
>Spawn Chance: 5%
Giant Ghast (Variant)
>Health: 20
>Ranged attack burst shots: 3
>Scale: 2x
>Spawn Chance: 5%
Optional Features:
Sleeping is for nerds!

I removed sleeping because skipping the night takes away most of the challenge of Minecraft. Now you must use think about how much time you spend outside more carefully so as to not waste it! Beds still reset your spawn point.
Addition of The Hunger Rework addon

The Hunger Rework is another addon I made that was always meant to go alongside this one. It limits how long you can sprint and makes food heal you when eaten. All Hunger Rework features come in a second pack when downloading becasue it uses the player.json file which sometimes competes with other addons. Plus not everyone likes this change).