I think that the people of the Sith aren't evil per se. I just finished watching that timeline on the holonet and in the earlier entries it says that the Sith helped each other with self sacrifice etc. I don't think the Sith are pure evil, just some of their 'villains'. The current Emperor has proved calculating rather than guns blazing and seems to take heed and not sacrifice his troops needlessly. Perhaps he ultimately wants to find peace. Think of the Sith Emperor currently as Thrall (sort of) and all its past, villainous leaders as Garrosh.
Tbh, the Republic's done some dog acts such as exterminating all the 'True' Sith in the Great Hyperspace War or whatever it was called. That genocide is pretty evil in my books. Also abandoning some systems when the Sith was threatening their core worlds was a weak effort.
With regards to the specific codes, Jedi and Sith; I don't think it's possible to have an 'evil' Jedi and 'good' Sith. They're pretty much cults and thinking any differently from the rules would mean instant exile. However the two factions are definitely not 'good' or 'bad'.