Last game, AC (bless his heart, he had to deal with so much craps from me), suggested the possibility of changing the amount of gold you get from Merchant fleets if you trade in other non Med area. This would promote historical accuracy.
However, at the time, I rejected it due the fact it gives non Med people disadvantages and adds complexity. Now, looking at it again, I feel it is worth looking at again.
However, I want player input, and I know perfectly well we argue like cats and dogs here, so begin discussing. The modifiers I plan to use are below
Black Sea -10
Indian Ocean/Red Sea -20
Atlantic Ocean: -20
North Sea: -30