How stats affects MC and EXP rewards

First of all MC got an EXP boost until lvl 5, this is because i'll make lvl 5 the normal civilians after they reached the age of 10. Thus MC got the boost.

EXP is pretty basic to calculate

-3 and under = 0% (they also won't be eligible for shadow extraction, can't make it too easy you know)

-2 = 2,5%

-1 = 5%

Same lvl = 10%

+1 = 20%

+2 = 30%

+3 = 40%

Up to +9 which is 100%, after this it will increase with 100% per lvl since i'll make it nearly impossible to win over someone 10+ levels higher.

Now the stats are:

Strength:

This stat will affect all muscles, generally increasing their power.

Perception:

This will affect his eyesight and other senses, pretty basic but i like it.

Agility:

Basically making him more flexible and affects how much control he has over his body, effectively it's both agility and dexterity combined to shorten the stat panel

Endurance:

This will change how durable his body is, i could've just called it defence but i combined it with stamina to have less stats. Know that unless someone uses a specific skill there are no impenetrable people, of course rocks and wood might not pierce them but metal always will. Exceptions are for example creatures with scales or something similar.

Vitality:

This affects his general health, higher VIT means more HP (1 VIT = 20HP). Additionally it increases his ability to heal wounds. Important thing to know is that a critical hit such as getting his head blown off or cutting a mjor artery will still lead to death unless treated immediately, for humans atleast. ;)

Intelligence:

Increases his brain activity making it easier to learn things, also affects his MP (1 INT = 20 MP).

Charisma:

This will affect the MC when he interacts with intelligent species, higher CHA will make him easier to believe as it affects how he speaks basically. Just imagine the skill checks from the Bethesda games. I am also considering making it affect a persons appearance, so that high lvl people will be more attractive. That is partially why i haven't started describing anyone's appearance, main reason is i'm not confident enough in doing a good job at it.

Luck:

Now this is where the MC will shine, only he has a luck stat that can increase and it will subtly affect the world in his favor if the opponent has a lower value. That's the current situation but i might change it, it is my story after all.