As far as the most moral posters go, there are a few candidates who are the most moral in a conventional sense:
Frodo
Ebowed
Keystone Phil
Gabu
Nym90
I know there are others, too, that I will think of later.
For least moral, I think the choice is clear: opebo.
Flyers2006 also exhibits a certain aggressive rejection of certain types of morality, as does BRTD, but I wouldn't go so far as to call them immoral. I think that their morals will evolve over time as they mature.
Well thank you for disagreeing with Frodo. What do u mean by "aggressive rejection of certain types of morality?"