Getting Carl to kill Lori was more interesting I guess, I mean, getting a sniper to kill her would give more of a revenge plot for Rick/Carl to get the Governor, but the Governor was wanting revenge on Michonne... So it makes it more than just about revenge.
Hershal I find was the replacement for Dale. He's walked right into Dale's footsteps as being the rational good guy the group needs. If theres more of TWD to come then I think he won't last long however, since his younger daughter has kinda grown up from Season 2 and has Maggie.
As Merle said, Carol is not the same as she used to be. She's stronger and the development would have had to been totally opposite, and I think she is important to Daryl because especially now that Merle died (I was surprised in that decision), he needs someone there for him. And she looks after Rick's daughter pretty good too.
Andrea's time was up, the majority of people never really liked her character that much anyway.
Carl's character had me laughing a lot, he just seemed to grow from being a kid to a lil man in like 3 episodes. He totally has a thing for Hershal's daughter too haha. Right on lil dude. He's bound to be trouble in the future.
Glenn and Maggie, they're just too strong as characters to die and everyone likes Glenn
Michonne... Wasn't a fan of hers at first but started to like her more once she settled into Rick's camp.
The new people, yerp they're pretty cool.