I'm sure people have had thoughts about having Respawn introduce other gold attachments and I for one am all for it.
Each one providing something unique and to keep things balance if needed, maybe only allow for one gold attachment to be placed on your gun at a time.
Extended clip that allows for you to use other ammo types for your current gun.
Barrel stabilizer I heard takes away muzzle flash and if so, I dont really notice. However if it doesnt, it would be cool to have it remove bullet trace.
Stock (Standard & Sniper ) allows you to run at full speed without having to holster your weapon.
Shotgun Bolt all I can think of for this is staggering enemies or simply give the ability to one shot a door and destroy it.
These are all just my ideas that I came up with on the spot, I really wanna see more gold items that make them unique in their own ways so that every gunfight is something to look forward too.