A weird lumpy limb that wiggled forth somewhere in d&ds many lives.
Often disdained, but generally forgotte.
And not something I've seen anyone try to "OSRify" .
I will do something with its wretchedness.
If you have spend anytime reading homebrew content you will have encountered numerous house rules for making weapons more complicated and differentiated .
So that it matters that a spear is long and an axe chops and a warhammer is really good for punching holes in plate etc.
The other thing you might read is rules for people doing tactical stuff in combat like "full dodges", "suppressing fire" , "shield bashes" etc
The trouble is these are often over looked, forgotten or neglected by players.
Which is BAD if you are perpetual tinkerer dm who wants to try out all these little mechanic options.
And you don't (and shouldn't ) want to have constantly remind the players about them.
However there is going to be some players that do care about it, and chances are they are playing a Fighter.
So making use of all this underused potential is give Fighters a form of Weapon Proficiencies.
Except I'm calling them Training Regimes , (Regime for short)
Dempsey Roll might be known to a boxer , but unless they have trained ,
sparred , and keep themselves in condition they will be unable to apply
it to its best potential.
A regime means the fighter has studied and regular trains in the use of particular weapon, weapon technique, marshal strategy, special move, new foot work , esoteric stance , etc
Regime will allow a fighter to , for example, not just use a spear like
everyone else, but use it with those weird reach rules you came up
They have one per level actively undertaken and practiced enough for it to be as second nature to them as drawing breath.
They can know far more than this, but they limited on how many they have available in their muscle memory and reflexes.
More regimes can be learned from studying books, sifus, weapon masters , secret schools and sometimes their own experiments. It will take anywhere from a week to a month to learn one.
They can swap a regime over, but it requires a week to get up to speed again with the techniques involved.
Examples of Fighter Training Regimes:
Desperate Defense : The "shields will be splintered" rule
The Long Stance : Always resolve your attacks first when you have longer weapon
Opportunity Knocks: Free attack with a shield bash if your opponent misses twice in a row
Cloud Step : If fighter does nothing but move and avoid attacks their base armour class is their dexterity instead of 10.
Le jeu de la hache : while using an axe 2-handed or axe type pole weapon , if this fighter reduces an opponent to zero or lower hitpoints , they can make immediate additional attack against someone/thing in reach . The benefits of this regime can only be used once in a round
This assumes any class can use any weapon or classes have a set list of weapons available to use. It's not another thing to spend proficiency on , but I guess it could??
Its also very similar to feats; however they can be swapped in and out in downtime and shouldn't stack or provide passive bonuses like feats. Some feats could be repurposed to this system though.
All Regimes don't have to be in equal in power, and some could even be better versions of more common ones.
The time and resources it takes to learn a new regime is going to vary on how rare and/or powerful it is as well.
Let how much you make wizard players sweat to learn new spells be your guide for how expensive or difficult it is to learn a new regime.