What I thought was (and still is) a bit ridiculous is Chuck´s habit to carry a tranq gun. It is in character, somehow, but a bit pointless when everybody around him are armed with real guns.
For the psychological effect “I didn´t kill him” in case they all would be forced to fire, is it a really poor excuse and it is just for an effect. I am sure Chuck is ready and perfectly capable of carrying a real gun (he got a CIA service gun after all, what happened to it?) and maybe even use it. I would like to see him deal with the killing again, but with someone who would stay dead this time.
It just looks, I don´t know, funny and I am not sure how can some other agents take him seriously when he runs around with a tranq gun. He is an agent now, "a real spy" as they say far too often, so they should make it work properly.
I know Chuck is Chuck and we like him for that, but when Casey handed him a real gun in "Cubic-Z", he was obviously ready to use it against Penzer so why the hesitation?