these maps look great! But they only seem to confirm my suspicion, that there's sth. wrong... Maybe it has been discussed elsewhere before, but: The Arbor exports wine to all the Seven Kingdoms and beyond, there must be many vineyards on the island - hills and valleys in a certain distance from the salty soil of the shoreline. Think not just the city of Bordeaux, but whole Acquitaine.
The same island has owned the biggest fleet of Westeros for centuries, further building warships for other armies. This means they must have a lot of wood - huge forests to provide for the shipyards.
And thirdly, there needs be good farmland to nourish all those dock workers and sailors.
I would conclude, the Arbor should be as big as Ireland, but all maps show it more comparable to Malta (at the most)... What do you think, is this a slip of GRRM?
Also, another question: The culture of the Iron Islands is obviously modelled after the Vikings. But if you look at it, they are (almost) on the same longitude as the Riverlands... The stormy, cold, weather of the islands seems a bit out of place. They are not really secluded (like Scandinavia in our world) either, you would think they should have been conquered long ago to stop them from raiding. Why did Martin not place them further North, off the Frozen Shore for example?