The Glen
Legend
This was actually one of my suggestions with the Wesley fighter. You have studied various fighting styles and can switch to the weapons to best handle the situation. 5e tends to give fighters everything (weapon prof) or almost nothing (fighting styles).fighter's number of fighting styles should be based off of 1+INT, in 5e fighter had access to 11 different fighting styles not counting 3 from unearthed arcana or the two druidic and divine warrior styles exclusive to ranger and paladin respectively, and a bog standard fighter would get only ONE of them, a SINGLE FIGHTING STYLE in 20 levels, not to mention most of them are mutually exclusive based on the weapon you're using barring a few like defense, blind fighting, superior technique or the shield syles, so you're not even able to stack bonuses for the most part.
the fighter as a martial master should be stacked with fighting styles.
Every class should have some mechanic that you get multiples of based on your INT. Would require a lot of rework for some of them though.