Ok, how about strip out Knowledge skills and checks. Then reduce to 4:
Brawn: Strength and Constitution
Dexterity: As-is
Willpower: Remaining Intelligence, and Wisdom
Fate: Charisma, Death saves, HP on even levels
You add your Brawn bonus (or penalty) to your HP on odd levels, and Fate bonus to your HP on even levels.
Paladins, Sorcerers, Bards and Warlocks are Fate casters. Artificers, Wizards, Clerics, Druids and Rangers are Willpower casters.
PCs get 2 good saves. Classes whose 2 proficient saves overlap get a good Fate save.
Death Saves:
A Death Save is a Fate Save. You do not automatically fail one when damaged at 0 HP or below, instead you make a death save with a DC equal to the damage taken. If you are hit with a critical hit, you make the Death Save with disadvantage.
Rolls of 20+ on a death save at the start of your turn result in you gaining 1 HP. Doing so in response to getting damaged does not do so.
Fate Points:
PCs can get Fate points. When you fail a saving throw, you can risk a Fate point to make a Fate save against the same DC; if this reroll doesn't succeed, you don't lose the Fate point, and can try again against another saving throw some other time.
Either the DM can hand out Fate points, or you could simply give each PC 1 Fate point when they gain a level (max 1; use it or lose it).
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I think this makes all 4 stats pretty competitive. Also, all of the Charisma save abilities really map over to "make a Fate save" reasonably well.
Brawn: Strength and Constitution
Dexterity: As-is
Willpower: Remaining Intelligence, and Wisdom
Fate: Charisma, Death saves, HP on even levels
You add your Brawn bonus (or penalty) to your HP on odd levels, and Fate bonus to your HP on even levels.
Paladins, Sorcerers, Bards and Warlocks are Fate casters. Artificers, Wizards, Clerics, Druids and Rangers are Willpower casters.
PCs get 2 good saves. Classes whose 2 proficient saves overlap get a good Fate save.
Death Saves:
A Death Save is a Fate Save. You do not automatically fail one when damaged at 0 HP or below, instead you make a death save with a DC equal to the damage taken. If you are hit with a critical hit, you make the Death Save with disadvantage.
Rolls of 20+ on a death save at the start of your turn result in you gaining 1 HP. Doing so in response to getting damaged does not do so.
Fate Points:
PCs can get Fate points. When you fail a saving throw, you can risk a Fate point to make a Fate save against the same DC; if this reroll doesn't succeed, you don't lose the Fate point, and can try again against another saving throw some other time.
Either the DM can hand out Fate points, or you could simply give each PC 1 Fate point when they gain a level (max 1; use it or lose it).
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I think this makes all 4 stats pretty competitive. Also, all of the Charisma save abilities really map over to "make a Fate save" reasonably well.