I'm only halfway through season 2 of the tv show (dragging myself through it because it's so much worse than the comics), but I really am unhappy with how they changed Maggie's character so far. Or maybe it's just me. I don't know.
I also wasn't a huge fan of how they changed Hershel, or at least how I read Hershel in the comic books...but it was more a tone thing than anything so I don't hate the character.
TV spoilers: Also gdi I wish Shane would just die already lol. I know he does but he's stuck around for far too long. Should have died halfway through season 1, imo. His actor is so bad and he's an annoying character.