The current system in which the game determines which of the four attacks are used feels very counter-intuitive. It feels like I have to move my coursor miles off the target to reliably get the attack I want.
I know other gamed did it the same way (Mount and Blade, War of the Roses), and it kinda works in those games, which means it could work in this game too. But there is a better alternative.
Instead of using the mouse as the thing which tells the game what attacks to use, use WASD keys. While W is pressed, the attack is going to be a thrust. While S is pressed, it's going to be an overhead swing. For A it's a swing to the left and a swing to the right for D.
Dark Messiah of Might and Magic used that system, and it felt cool and intuitive. Overhead means you move your body weight a bit back to, thrust means you move your body forward to put your momentum into it.
(Or at least, copy the system Chivalry uses)