@Titan224 Sorry if I'm going too long here
Vandalieu does not give punishment to innocent people, in fact, if he sees a soul that wants revenge, he would be more on the side of "Ok, I will help you", he also has no problem killing people, although that's usually focused on people that try to kill him, or people that are serving as obstacles. He won't proactively try to kill people, unless he decides that "they deserve it", and as shown in the village, sometimes, death is just not enough, it's better to make them live while suffering.
The point is more that he doesn't see death as something big like we do, not only this is the attribute he uses, do keep in mind that unlike the usual stories where only special people meet god and that's when it's relevant, he knows that everyone who dies just goes back to revive without memories and stuff.
Unlike Overlord where the character is considered evil but runs on misunderstandings and extreme luck, Vandalieu is the reverse, he is treated as evil because he is insane, his common sense is completely irrational to many others, he is not lucky, in fact, he is more on the unlucky side, but he is an "hard over worker", he is also over protective towards his family and friends, a paranoid towards danger, and "freaky" against his enemies. Think of him being molded over an Horror film character like The Ring's Sadako or The Grudge's white kid.
This is not a Shonen manga, rather, it's a Seinen, it requires you to have your mind open a little to a medieval fantasy swords & magic rules with monsters, multiple races and gods, and not only that, as mentioned at the start, this is the world resulted from a war against the Demon King 100K years ago by the 7 Champions. Don't expect this world to run like Japan, nor expect the MC to try to turn this world into Japan.
The people who burned Darcia did that over their religion, but unlike other stories where there is an excuse of religion being corrupt or some sort of evil master mind who wants to dominate the world, this is not the case here, the religion follows exactly what their God taught them, and more than that, what those old ("Japanese") Champions that survived the Demon King taught, and that's where the fucked up stuff from this world really started.
This is to give you a better idea if you want to continue or not. Although more aimed towards the novel, the Death Mage Subreddit has a FAQ for new readers that are in doubt about what the story will present them, this is because by the summary, one would expect an edgy hero, revenge plot and stuff like that, but the author here likes to subvert many tropes.