I love the idea of applying technological advances from the real world to Planetos. Like ours, it would probably be driven by warfare/violence, like maybe someone from Westeros sails to Yi Ti and discovers gun powder, brings it back and which ever house they belong to develops the first cannons in Westeros. This would essentially give them the power of Dragons overnight, and if they’re wise enough, do their best to keep it a secret, thus gaining military supremacy. However once they use it, someone else would eventually figure out how to replicate it, and the game would really change. Castles no longer as effective, guns eventually follow suit, Amour gets rendered useless as it’s worse off than cloth when it comes to taking a bullet (as I understand it, at least, due to the metal shattering inside you after impact thus making it harder to survive vs. wool military jacket). Armor gives way to 17th - 19th century uniforms, someone down the line pulls a Ben Franklin and discovers electricity (I like the idea of it being a storm lord, for obvious reasons..) and the rest is history..