It depends on the situation. If it wasn't for Shane they'd still be looking for little dead Sophia and arguing on if they want to keep that dude alive. Shane was right in both those situations while Rick was tearing the group apart with all the arguing and stalling. Other than that Rick's leadership has worked best.
Not really. Rick was trying the "go along to get along" route with Herschel in an attempt to ease the old dude into accepting the reality of the zombie apocalypse and was going to be taking up Otis' slack by corralling zombies and putting them in the barn. I'm sure he'd have noticed Zombie Sophia shuffling around in there sooner rather than later.
And Shane gets no credit for offing Randall, he only did that as part of his hoish Fatal Attraction scheme against Rick.
Didn't Merle say that they were supposed to rob the original crew before Rick showed up and Merle got tossed in the bushes
Yep...Meryl would have had a rape orgy with Carol, Lori, Andrea, Amy and that black chick while Daryll would have been wearing Shane's earlobes as necklace if Rick didn't show up and straighten that group out.