Please make a unified gameboard or -mat, I am willing to pay the price for it if that is the issue.
Don't joke with the freaking track in the middle of a board...seriously...
Sell the map separately if you don't want to place it in the original box.

If you fail to do these things above, please make a high resolution unified map downloadable so the real fans can print it themselves at a local print-shop.
If you fail to make a downloadable map available, you know fans will create the map by themselves and place the file at Boardgamegeek.
So do your fans/customers a favour and make a downloadable high resolution unified map available.