This would be a mod that fixes the quickdraw while playing in mouse and keyboard on pc. When playing in console, you can just press the fire button while your gun is hostered to quickly quickdraw without having to unhoster your weapon or aim at peds, in pc you need to improvise and while focusing in a ped with RMB, quickly press LMB and stop pressing RMB, then tapping again LMB, which is not pratical.
This mod would possibilitate to simply quickdraw your gun (without using deadeye) by tapping LMB one or two times, which would probably make impossible to punch using LMB, but giving a good and pratical tool to firefights.