In my world, there is an "evil" empire trying to expand its rule. However, in reality, they are just like any other empire expanding. Despite this, I still want to make them like a force the protagonists need to defeat.
When trying to create it, I suddenly realized that I ended up making it way better and less corrupt than the main kingdoms. Though this does sound like a good concept, I am trying to make it so, story-wise (but still worldbuilding), the empire is a greater evil than the smaller corrupt, feudal kingdoms and citystates. What are some ways that the evil empire can not be all that bad, but not too humanized?
For facts about them I have for now:
The evil empire is based on the Ottoman Empire in their golden years, and also some Mediterranean influence
While they are intellectual and socially ahead of other kingdoms, having gender equality, racial equality, and lgbtq rights, they are ruthless and brutal in warfare
They do not really have any rules of war or chivalric codes, so they are seen as animals when it comes to war
They offer smaller nations the ability to peacefully join, but if they refuse, they will mercilessly butcher their military and destroy their cities
Like the Ottoman Empire, they will allow the practice of outside religions, though will have a tax on it
The empire is highly Jingoistic, and as mentioned above, are highly expansionist