I noticed that if there's no copper wire present in inventory, pressing the shortcut bar creates one out of nothing.

Could I suggest changing the behaviour to make it trigger crafting, or greying out the button if no copper wire is found?

Basically, the idea is that, for purposes of connecting things, wire is as good as free anyway, so make it actually free. It's mostly focused on red and green wire, copper wire is used for connecting things very rarely. But for the rare occasions when you want to connect something with copper the mod will give you that one wire if you don't have any lying around. If it triggered crafting it would a) potentially mess with people who care about what they handcraft (going to the achievement or something); b) potentially be stuck in a very long queue; c) probably leave an orphaned wire in your inventory as you craft two and use one. I think one wire from nothing and only if you don't have any already is fine.

Fair enough