So, playing the third mission took far too long time when you had the gold since clicking on the gold in your coffers to place it in the smelter is tiresome.
Suggestion: Make it so that if you hold the left mouse button on a goldstack in your coffers that it starts picking up gold for you automatically until you have maximum in your hand. Same for dropping gold.
Example from the game: https://youtu.be/DghcSDbMdeI?t=21m50s
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