I just thought about the keys F1 - F12.
In other rpgs you can put special items on this keys and you need no longer enter the inventory to choice the letter.
F.e.
F1 = Bashing weapon
F2 = Handgun
F3 = Shotgun
etc.
In my current game I often switch between Alu Bat, Katana, Pistol and Rifle. (I don’t know if it’s already planned.)