A song of Fire and Ice reloaded. There should be a much greater variety of weird creatures in Westeros. I'm thinking hoop snakes and Goldenaxe-type beasties! And the Maesters actually invited the Targeryns to invade Westeros. In their citadel at Oldtown, the Maesters have access to highly advanced technology. They are able to access most Maester's residences via an advanced underground tube network. The North, meanwhile, has the remnants of a railway line. The dragons, it turns out, were all killed by the Targeryns' efforts at industrialisation. The tactics used by the Westerosi really ought to reflect the (past) existence of dragons, so a main development would not be mounted knights (heavy cavalry) but light mounted archers. Heavily armoured knights would be used only as a kind of police force to quell rebellions. Training for this would be the tournament, which would hold jousts. Perhaps the term "sheriff" would be used; or perhaps ...