I would tie it to difficulty. The normal difficulties should have some streamlined ammo creation, hardcoe should have the complex system.
Also, the interface is WAY too clunky. The workbench model just doesn't function well with the large goofy console-UI and multiple ingredients then pressing "a" to process for some reason. Thanks for taking us down three pegs, consoles. Even Dead Rising 2 had better weapons creation.
I'm just not happy with the end result; too much effort for the outcome.
