I recently unlocked mushroom stew (Yay!), but I also need to make mushroom paste on a regular basis. It would be nice if we could set a reserve stock of items in our inventory so that the game won't craft with X amount of the item. For example, if I could reserve 500 mushrooms, then those would still be in my main inventory for using for quests and cooking, but those 500 wouldn't be usable for crafting/the craftworks. That way I always have my reserve on hand for what I wanted.
This would also be a better way to handle quests that require fish, since a quest that requires a common fish and a rare fish from the same area will create a hassle if you don't want to void the common fish.