There are existing RPG rulebooks that address these sorts of questions to various degrees and in the context of their various resolution frameworks - for instance, Apocalypse World and Dungeon World; HeroQuest revised; Cthulhu Dark; Marvel Heroic RP; 13th Age.I think the issues is degree of success and argeement of who has better odds in certian occassions.
For example, you can say all the warriors could be 2 dice characters.
But who has the advatange vs a mob of mook goblins? The strong warrior with heavy armor and a great-weapon OR the fast warror with light armor and 2 light weapons OR the sorta strong sorta agile warrior with the big shield and a long spear?
What about when they are fighting a single big ogre?
What about a pair of orcs?
How do they compare to the unarmored unarmed warrior using martial arts?
Such simplistic rulesets or low class number RPGs tend to sit around gameplay that doesn't get deep into specific areas nor allow for changing variable to be part of the challenge. They rely on everyone quickly agreeing on the logic behind the game. If total agreeming on the logic and how the tropes interact isn't quick or clean, they don't work. And D&D runs on a lot of tropes.
Just as early versions of D&D gave the GM a lot of advice on how to introduce traps and tricks into the dungeon, and how to adjudicate them fairly, so may this imaginary version would give the GM a lot of advice on how to work with the group to adopt appropriate descriptors, how to manage the relationship between fiction and action declaration, etc.
5e D&D already has aspects of this as part of the game - for instance, when does it make sense to call for an INT rather than a WIS check, or a STR rather than DEX or CON check, etc - so it's not as if it's completely foreign to the spirit of D&D as it actually exists.