I dunno. Season 1 was really accurate but Season 2 had all those dumb changes. Jon Snow's plotline in particular got butchered beyond belief.
I did like a few of the changes. The scene of Theon contemplating sending a letter to Robb wasn't in the book.
Yeah, I don't mind changes like that, which just strengthen and flesh out an already existing plot line. There's a big difference between that and, say, cramming the beautifully paced Jon Snow plot in ACoK into a single ep so they could have an ep of him and Ygritte wandering around and flirting or completely changing the Qarth storyline to the point where other than the names "Xaro Xhoan Daxos" and "The House of the Undying," it has absolutely nothing to do with the one in the books. Seriously, their take on the House of the Undying scene frightens me more than anything. The scene in the book is basically a blueprint of where Martin is going with the series and... they didn't include a single, NOT ONE, image of moment from the book when adapting it. Really makes me worried where the fuck they're going to go with it.
Was about to say that I think that's down to the books rather than the series, and then realised you've read the books. Still, there is an ongoing problem that they can never match the surprise of... ahh, episode nine, season one.
Eh, it's a great moment to say "This isn't your daddy's fantasy series!" but there's a lot more powerful moments and surprises later in the series, IMO, especially in A Storm of Swords.