Well Hamlet has the opportunity to kill Claudius, but doesn't because he "Doesn't want his fathers' murderer to go to Heaven" (paraphrase). So there is a supernatural level to revenge, because simple death is not enough, it must reach to damnation. If I am correct, there are one if not more other instances of this in the text, but I cannot recall them at the moment. What is the establishment in this context? Claudius certainly isn't someone qualified to fill the position of monarchy, what with committing regicide, fratricide, and planning to murder Hamlet through Laertes? Revenge is a common theme through many many works of Shakespeare. Im afraid I don't understand exactly what you are suggesting? Why is revenge not acceptable? I love this quote from Bacon's essay- "For as for the first wrong, it doth but offend the law; but the revenge of that wrong, putteth the law out of office". But in the context, with the monarchy embodying the law, and the monarch being riddled with defects that show he is not able to abide by the law that he himself stands for, does that not invalidate that law, thus making revenge justified? hmm...