Some things I think would be beneficial for when trading is implemented:
1. Double Confirmation UI
In order to prevent possible misunderstandings or blatant scams, I think it will be more than necessary to include a two-stage confirmation process for both parties. It would work as follows: both pirates add their proposed items to the GUI, similar to how we see it work while selling at NPC vendors. Both pirates can see each other's boxes as well. Once a pirate is satisfied with what he/she decided to trade, they select "confirm." Once both parties have confirmed, the proposed trade is now "locked in" and displayed again to both pirates. Both pirates can review, hover over each item to ensure it is what they want, and then click a secondary "confirm trade" button. This can prevent last minute malicious swaps of, say, Barracuda Blade for a Spinecrest without the other pirate noticing. On top of this, I think it goes without saying that altering trades should un-confirm the other user involved in the trade. This is common practice in other games with item trading.
2. Internal "Trade Whisper" Designation
Another implementation (granted, not related to the user UI) could be automatic flagging of all whispers between players after a trade initiation as "trading whispers" internally. These chat logs can then be directly linked to trade history for easy moderation access if problems arise down the line and someone submits a report. Not sure how helpful this can realistically be, but just a thought.
3. Polyitem Trading
I don't think trading should be restricted by item type, say, weapon-for-weapon only. For trading to be interesting, I think all item types should be allowed to be added when trading. If I'm trading a Black Shark Blade for a Seven Seas Cutlass, I might want a Dark Black Cotton Gaucho to sweeten the deal. It'd be nice if similar scenarios were possible.
4. Only Include SF/Patron
The looting community has thoroughly voiced their qualms with trading in general already, so I won't add to that hysteria. Center stage in that argument, though, is the removal of legendaries from trading contention. I think this should still happen, but I believe that The Lost Sword of El Patron and Silver Freeze can be fair game due to their rarity more closely resembling that of Famed weapons. I suspect the looting community would agree!
5. Mark Traded Itemcards
An idea was shown in the past where item cards would have a small tag on them prior to trading, removed after the item is traded so to designate it as "traded" or, some might say, AKA "worth less." The idea is on the right track—just backwards. We need to keep item cards of untraded items unmolested. Tags should only be added to traded items.
Thanks (seriously, thanks!) for letting the community add to the fun! Good luck team!
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