I think any Zombie TV show keen to talk psychological, philosophical and social commentary is fairly unique not wholly but it is sufficient enough.
Endless cliches? It is a Zombie TV show after all. However there are a few twists and as yet the viewers are still in the dark about many aspects of how, why etc. Now a cliche would obviously use aforesaid plot and scenario from other media in this ilk but we are yet to know full details...
So i'm not allowed to debate with you and bring forth material as to why you are incorrect based on the aforesaid script incorporating characters and their symposium on moral obligation, philosophy and such forth? Argument, point of view, debate they are all interchangeable words to denote the nature of our communication upon this subject
Again, please note I am not ear-marking The Walking Dead as a piece of TV history like The Sopranos but I think you do it an injustice to say the script is poor considering the range of topics covered etc.
FWIW, the end of Season 2 redeemed itself as the beginning of the season seemed to be heading for overplaying the morality of the situation and the consequences of the characters and their actions.