My biggest gripe about Palpatine was that he didn't live by the Sith way. The Rule of Two was this: When the apprentice became strong enough to kill the master, they would do so. If what Palpatine said was true (which as a Sith is entirely possible to be false), he killed Darth Plagueis in his sleep... That's not the way it works. By doing this, you make the Sith weak and able to be destroyed... just like they did. Now... maybe he was stronger than Plagueis by then... but why kill his master in his sleep? Why not do it the right way?