D&D (2024) Dropping armor proficiencies and using Strength as base for armor use.

[Mistwell]

everything else is level 1 or 2 filler until you buy yourself armor you want/need; padded, leather, hide, chain shirt, scale mail, ring mail, chain mail and split are waste of space in PHB.

It's a cost issue. Breastplate is 400 gp. You're not typically buying that at level 3. I still have a PC around level 7 who can only a that point even consider buying anything more expensive than scale or chain mail. None of the guidelines for wealth would match level 3 for the types of expenses you're talking about.

Regardless, if you're going to change it the ADD INTERESTING PROPERTIES. Why would you make it simply a sterile scaling chart?

 

[rules.mechanic]

Should 1D&D just drop armor category proficiency and just use MIN STR stat for all armors?

It would give more importance to Str as an ability.
having effective Dex mod to a degree for even heaviest of armors also prevents "free" dumping of dex to 8. you would want now atleast a 12 for optimum AC.
Also Dex damage effects would now be impactful to heavy armor users.

Armor name	Min Strength	AC bonus	Max Dex
Leather	10	+1	+6
Hide	12	+2	+5
Chainmail	14	+4	+3
Half-plate	16	+6	+2
Fullplate	18	+8	+1
Buckler shield	12	+1	n/a
Shield	14	+2	n/a

penalty for not having required STR for specific armor would be:
speed halved,
Disadvantage on all attacks,
Disadvantage on all STR, DEX and CON saves and checks,
All targets of your DC based abilities and spells have advantage on their saves,

Why not simply say that you cannot cast spells?
For simple reason that a simple STR drain/damage should not be complete removal of caster from battle.
This way you can still heal, buff or chose to "misty step" yourself out of the armor. Trading protection for normal spell usage.

Instead of adjusting max dex, could you not just say that dex can't raise base AC above 17?

 

[tetrasodium]

Instead of adjusting max dex, could you not just say that dex can't raise base AC above 17?

That introduces some of the inanekind of ac problems 5e barkskin has