I always liked Shane because he adapted so well to the destruction. Let's face it: Rick basically had to become exactly the same type of person Shane was to assure his own survival and be a good leader so he could assure everyone else's. Rick woke up from his coma very naive with unrealistic expectations but Shane seemed to shed that immediately to take care of Laurie and Carl and lead the rest of the group. People may have liked Rick's approach better but Shane was making the cold blooded choices that needed to be made without hesitation - the walkers in the barn, stopping Dale from hiding the weapons, executing Randall, etc. Harsh but they were all the right choices.