Currently using a crafted weapon just levels infinitely with 0 benefit after level 30 (I thought it capped at 20 but apparently 30 is the final stat bump). I would propose at level 30 give crafted weapons the Gold Masterwork border. Let players have a visual indicator of essentially "congratulations you have used this weapon enough to max it out". It's such a little thing but I, and I think many others, like to feel rewarded for their investment into a weapon and making the gun have a tiny extra "something" would hit that spot; in my brain at least. Ymmv but I think it would be positively received.