Damn, I like the manga much better than the anime. Here's my reasons why;
1) The artstyle is better(The anime's artstyle looked generic af, the LN artstyle that the anime is based off of is really good but the anime itself doesn't even begin to compare)
2) The fight scenes are better(The fights in the anime are extremely watered down when compared to the source material - the LN, unlike the manga)
3) The spells look better(The spells in the manga actually look good, and look powerful. In the anime however, they look... Idk, generic? Meh? They just don't look very good)
4) The manga more accurately portrays how powerful Anos and the other powerful characters actually are(There are 2 main examples I can use; [Chapters 10-12, Episode 4]Anos vs Time God and [Chapter 14, Episode 5]Anos and Lay vs The 2 Elder Demon Emperors respectively. These examples don't really need much explaining as long as you compare how the fights went down in the manga vs in the anime. [Anime Version] The Time God's attacks look weak and unimpressive. [Manga Version] The Time God's attacks actually look powerful. [Anime Version] The Elder Demon Emperor that Anos "fought" got off-screened while the one that Lay fought got pathetically knocked out in a single attack. [Manga Version] It's explained that the Elder Demon Emperor that fights Anos was powerful enough to split entire mountains with a single slash. He strikes Anos' head with mountain-destroying power, only for it to do no damage to Anos. There is a somewhat long battle between Lay and the Elder Demon Emperor he's fighting. The Elder Demon Emperor's fire sword instantly burns any sword Lay throws at him to ash while his ice sword instantly freezes them. Internal monologue reveals that he can strike 200 times in a single second. Lay parries all of his attacks with wind pressure before destroying his fire and ice swords, leading to his victory)
5) The pacing is better(Pretty self-explanatory, the pacing in the anime was fine for the most part, but could've done better in some areas)
6) The characters actually have expressions in the manga(Technically, the characters do have expressions in the anime. What I mean to say is, they aren't very expressive in the anime, especially in situations where they should be. For instance, when Anos calls Emilia out for having a noble steal the scepter in the manga, she looks terrified and shook. However, she has no reaction whatsoever in the anime)
I don't hate the anime by any means, but it definitely could've been A LOT better than it was. Honestly, the only thing I liked about the anime were the VA's.