If you're considering reading this, perhaps the biggest consideration is whether you can accept MCs that show too much mercy as a plot device. MC is very passive, to the point where it endangers his allies. He himself is OP, so the author uses his weaker allies being in danger to cause tension... but this is only made possible through MC's unreasonable inaction. There's also an annoying amount of characters who repeatedly threaten the MC and his party, and the MC ignoring them. While one may attribute this to MC's ability to judge that they're just saying it as a front and have no ill will; it's quite unreasonable to completely take it at face value literally every single time... and this actually becomes a problem at some points where his party almost dies.
MCs are both OP, but Satou is more so; but it doesn't really matter since both are barely threatened by anything. The main threats are towards their surroundings.
In the case of Satou, he creates a persona as a scapegoat for when he does OP things. Sirius just wings it and it results in his identity getting revealed a few times.
Satou, aware that his party isn't as OP as him, prepares many things for emergencies. Sirius... nothing...
The first time Sirius's party almost died was when Gremory brought in some murderers into the school they were at. He was already aware of Gremory's character, and he was also aware the Gremory isn't above using his students, as he saw during the duel thing. So when his two disciples were challenged by students from Gremory's class, what would one expect him to do? Well, whatever you expected, he actually does nothing. Later on, it's even revealed that he saw that the aforementioned students had some suspicious people in their party, but he just ignored it.
While the author tries to develop Sirius as a decisive character; he forces Sirius to inaction in order to move the plot. I actually had some expectations when Sirius said that Lior was indecisive but turns out author made MC even less decisive than Lior.
In the case of Satou, although he shows a very pacifist attitude sometimes, but it's not excessive and iirc never to the point where it endangers his party. In the most recent chapters as of the writing of this review, he killed a Demon Lord who he identified to be a reincarnated person. He also frequently acts as an advance scout as Nanashi before he goes around touring. In emergencies, we've seen his main priority is to bring the fight away from his party (as with vs. Dog-headed Demon Lord). When faced against potential enemies, he has shown some initiative in tracking them down instead of playing it passive (as with the various terrorist organisations).
Sure Death March has its flaws, but those are for a review of Death March. The points I brought up are things Death March did right, but was ignored by World Teacher.
They both are strong and ultimately never fail to protect their party, but there's a clear difference in how the authors choose to move the plot. In this regard, I prefer Death March as it sticks to its premise. Although you can argue that Death March's premise has Satou being too OP, I'm the kind of guy who can more easily accept stuff as long as its established in the premise of a story. If I'm unable to accept it, I'm able to drop it early and develop no bad feelings towards it.
With a crazy MC, a first-person perspective can allow MC to be an unreliable narrator to great effect. Instead, we get a 3rd person narrator but with MC interrupting very often with long-winded monologues.
With very skewed stats, this could've been justified much more with an automatic stat distribution system. As of v2, we've only seen two characters invest in stats from levelling. Both choose to invest in only one stat.
among other things