Horwath
Legend
6 abilities is too much.Homebrewery is where it is at.
Sadly, after 5 editions of the game, the team at WotC has been unable to crack the unevenness of 6 Attributes/Abilities, whatever you want to call them, and they mostly rely on DMs to fix the issues they cannot.
That said, people are not strict enough in their games on Encumbrance and I imagine Attunement, but those only move the dial on fairness so far.
The more you have, it's less of a cost to dump one.
if you reduce abilities to 4 only you get more balance:
Strength:
Current STR and CON saves, call it FORT save
Bonus HPs
Carry capacity,
All armors and weapons have MIN STR score to use
Melee and thrown attack and damage bonuses
Athletics skill
Dexterity:
Current DEX saves,
AC bonus
Finesse and ranged attack and damage bonuses
Stealth, Acrobatics, Thievery skills
Willpower:
Current INT, WIS and CHA saves
Spell attack, damage and DC bonuses
Cunning:
Bonus languages and/or tool proficiencies
All current INT, WIS and CHA skills