Imo, there should be a menu option to enable or disable automatic weapon switch. There should also be a weapon priority list where a user can customize which weapons he prefers most by sliding the weapons up and down the list. If a weapon has a greater priority then the game will automatically switch to it upon pickup. This is how I attempted to program it in the weapon project. There should also be a list of disabled weapons - these never get switched to. This is how most modern games handle the weapon autochange feature.