I don't remember who said it or where, but someone had a surprisingly simple, yet great idea:

The existing trading interface would be almost ideal for transferring things between party members.
  • You could see what the other person has
  • You could transfer items to them in bulk instead of dragging them over one at a time
  • Possibly, you could even make use of the convenient Identify and Repair buttons there somehow, if one of your other party members has points in a skill that you don't.


I'm not sure how easy it would be to implement it, though AND have it work for both single player and co-op. You'd need two "Okay" buttons in co-op instead of the single one used for merchants.

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New one for the list:

If a merchant has a stack of items for sale, the price listed should be for ONE of the items, not the entire flipping stack.