Ellri said There are two things in particular we truly hope will be discarded in the revisions of the Star Wars universe... The Sith tendency towards Speciesism and suppression of females.
Speciesim although illogical for the empire as a whole makes sense in terms of keeping a stronger and more pure bloodline that commands the force better.
It basically becomes a quality > quantity deal. Just that they lose so much quantity it's suicidal for almost any tactic outside of the rule of two (which was a fairly poor system itself though).
The sexism I agree makes zero sense in terms of power and efficiency. But treating women as second class was common practice in most empires of all of history, it's realistic for some organizations in star wars to be the same way.
Revans Exile said Sith aren't about being evil against others' good. They're about the ends justifying the means and having to obey all sorts of long lists of rules. Independence, really.
That's more Revan's and Kreia' territory.
If you asked the Jedi or something the two are definitely evil, but in truth they were more of a gray. End's justify's the means, don't go too good or evil, simply use the force and tactics in the most efficient way. No bias, use all your resources, harness all sides of the force etc.
The Sith and Jedi both restrict themselves to certain codes, rules, traditions and area's of the force to specialize in. The Sith may be more willing to take extreme's to reach their goals but they're not grey area, harness all the power either.