Chaosmancer
Legend
Proficiency is not mastery.
It is the mark of being a skilled professional, and outside of combat styles and feats it is the limit.
So, what is proficiency to you then? Should we allow weapons to be Expertised? I can tell you, in bounded accuracy, giving a character a +6 to hit to make for a +17 leads to VERY boring fights.
That's core issue pushing the Supernatural Martial.
Because D&D is almost always completely designed around low levels. It's designed to created town guards, skirmish vets, and low scoundrels. The early class chassis is designed around though. Then you hit level 10 or so and run into big giants, demons, and dragons. But you are still running a town guard just with higher numbers.
So you say "My high level town guard is supernatural and can catch the giant's boulder" in lieu of actual features and to explain the situation.
Instead of "My warrior is so good at combat, a clumsily thrown boulder isn't going to hit him if he sees it coming"
"What about 3 boulders?"
"What ABOUT 3 boulders? I spent downtime sparring 5 v 1 with a fey princess's royal guards who have permanent glamors. That's a ROCK!"
sigh So we are back to wanting the exact same things, you just want to insist on calling it your specific definition. Unless you want to go back to 3.5 numbers where at a certain point no one bothers rolling dice because they need a 50 to hit you on the d20.
Because here's the immediate problem. Let's say I gave the Fighter a feat called "Untouchable" that allowed them to use a bonus action to make all attacks against them have disadvantage... that is a bonus action dodge. Monks use ki to do that, therefore that is a magical ability and it should be limited, how dare I break the game.
And that ALSO ONLY covers combat. My 15th level fighter getting hit by a giant's boulder is fine. My 15th level fighter approaching exploration with the attitude of "well... I can walk into the traps if you want?" while waiting on the wizard to cast fly on them so they can carry the bard who will cast invisibility so they can yadda yadda yadda, is not fine.
I want new abilities for the classes, and if the only way to get them is to demand they be supernatural classes first, fine.