The balance is great actually. Imagine you find the ultimate ancient treasure sword which hits a little harder or has a poison effect, you confidently board a ship with the goal of causing havoc, they end up gunning you down anyway, you fade to a ghost and leave your sword on their deck. On one hand you had an upper hand bringing that treasure weapon to the fight, on the other hand, you just delivered a $2000 gold weapon to their deck and now they're leaving with it, fully planning to deliver it to the weapon npc for money. These little things just spice up the game options and make using one or killing someone with one just a little sweeter.
They could be turned in for money using the weapon shop npc, which so far has no turn-ins, this update would change that. But it would be very interesting to change up a play session where finding one changes the way you play the game or the way you approach combat. Ultimately it just spices up the world and the kinds of items you can find while making the game more fun without breaking anything. It doesn't make sense that I can find cups and chests and not a masterwork sword in the hands of a skeleton on a deserted island, etc. Or perhaps another thought. These things randomly spawn around the world, and the discovery of a special sword or gun is what unlocks a new sword skin, or weapon skin. Over time you could have pride by using rare skins that are only obtainable through rare discoveries. If you get cut by a treasure sword, now you unlock a new scar too. There's a lot the game could grow from this addition and it blends the excitement of pve and pvp because you need to search the landscape to find one in the first place and then you have motivation to attempt pvp with it, or just use it for monetary gain, the playstyle is up to you, but it opens new doors and gives players something new and exciting to look forward to when boarding an island or cheering with your mates after killing a player with a shiny weapon.
