Don't know if its intended (god help archers if it is) but making arrows in carpentry gives 1 arrow at a time instead of an arrow for every plank in your backpack.

It is working as intended. I was also considering a menu of some sort to allow the crafter to input a specific amount to make instead of 1 at a time or all at once. What do you think?

Sounds great, definitely would be useful.
Could do something like a dropdown menu when you click the arrow on crafting that lets you select how many to make (ex: 1 10 25 50 100 All)