Originally posted by LordOfTheDread:

I personally very much dislike the wishbone mechanic and I think silver is by far the worst metal to grind for.

I dislike the Wishbone too, but only because of all of the useless 'treasures' it notifies me about. Once you have bought what you need from the Trader, all treasures are nothing but junk and not worth my time.
As for worst metal to grind for, for me that would be iron. That is because you need so much of it and even in the end game you have to keep going back to the swamps for more. Silver by comparison is a short term and finite chore.