Simple suggestion really. All item related weapon sprites would be editable INSIDE their respective item in the item editor. A new tab would contain a list of related weapon sprites.
For instance, the Sword 1 (Wooden) item would have the following list in it "Item Sprites" tab:
Sword 1 (Wooden)
Sword 1 (Wooden) Slash
With this system in place, not only would clutter be reduced, but you could have independant weapon sprites for new items!
For example, you create a sword item (z222), and add it to the Sword family. It would then contain this list:
z222
z222 Slash
EDIT: This could be further elaborated to allow for new sprites to be created within each item, which could then be displayed by the item's script!