I'd definitely like to see more fighting styles that give options to certain kinds of fighting, but don't lock character into a particular weapon. Ideally, your fighting style would give boosts to multiple methods of fighting.
Like, personally, I'd change GWF to any weapon, not any melee weapon. I'd change Archery to "ranged attacks with a weapon", not ranged weapons. I'd change Dueling to +1 with any weapon that isn't two-handed, so it stacks with Two-Weapon Fighting. I'd combine Two-Weapon Fighting and Protection, and let that style also treat a shield as a light 1d4 bludgeoning weapon. That sort of thing. Basically, encourage style swapping.