True, but as someone who sits at the top and has the power, it is important to know when to be kind, when to be cruel, and when to be human.
Based on all i have seen in the story, she only knows how to be human and how to be cruel. Her kindness is not kindness for her people but a form of exchange for all that they have done, and her cruelty isn't just for punishment or the enemy but also to "encourage" her ally. Even her "love" for her son and the effort to make him the king is just her way to keep be in control when the emperor dies
She is not a benevolent ruler the peasant will love or is she a wise ruler who knows when to be kind and when to be cruel. She is a heartless ruler that rule upon others using fear. So I will fault her behavior not because of the "evil" she has done, but the good she didn't do. "A product of the circumstance" is not a good enough excuse to give her a free pass for not treating her own people good.
I would have agreed with you if she cares about her dead father a little, like a little break on her mask when she hear the news or something. Sadly, even the acting duke Ivan didn't see anything in the novel (chapter 142 btw if you are curious), hence why he is afraid and think the empress is dangerous. Someone who shows no feeling to her own family will not show kindness to her ally after all