So, an edited version of a textmessage log between me and nextian:
me: I think another big GoT TV vs. books difference is that for predictable but understandable business reasons the show promotes an Everyone is Gray Pick Your Team Who Will Win??? relativism whereas the books are actually very sharply colored by authorial morality with very sharply virtuous and nasty decisions and it is never unclear who are you Meant to Root For, though it changes. The books have a lot more of the feel of Epic Tragedy Melodrama with Tragic Flaws: readers think they’re morally relativistic because they’re violent but they are really not—however, more of an evenhanded ensemble is suited to TV than a clear set of authorial messages.
Which I agree with—it’s quite possible the book Lannisters would have made tedious and painful TV. You don’t have to spend a ton of serialized time with them in the same way reading. TV has to give you a lot of character options to invest in—books have to pick a team, and these are no exception. This means GoT viewers express a degree of uncertainty/belief that a team will “win” which puzzles me until I realize the show doesn’t underline the same heavyhanded anti-LotR All Power Corrupts message.