Linking each world's market board on the same data-center would be nice for many reasons, but of course the only ones who will complain are the greedy self-centered control freaks.

And its not hard to make all the Gil you ever need with huge amounts of competition, the more selection, the more competition, the more items that sell and continue to sell. Yes, you wont be making profits of 1m per item, you'll have to settle for much less.