I question the value of having weapon parts at all since T6 isn't craftable. So once you get a T6, unless it has terribad stats, you probably won't have a need to craft that weapon anymore. Almost every other crafting resource is useful in some capacity regardless of gear and level, but weapon parts gets obsoleted.
I've posted the suggestion before of having a recipe like T6 weapon + ~20 weapon parts = New T6 weapon with different stats, letting you reforge your weapon and giving parts extended value.
Could also try to reduce the number of parts by making it one part per attribute. It may not be the most realistic idea, but it could be like;
Precise Parts = Rifles, Spears, and Rocket Launchers
Heavy Parts = Shotguns, Clubs, and Sledgehammers
Flexible Parts = Pistols, Bows, and Machete
Durable Parts for Fortitude
Advanced Parts for Intelligence