I'll start by saying it's a good watch overall. While the whole "being trapped in a video game" thing is tired, this book adaptation does well in execution. The characters are well acted, the story lines interesting and complex (usually in a two-faced political sense), and most characters likeable.

Now here's where the show falters for me:

1. Much of the show (especially the second season) actually kicks Ains's story to the side to spends several episodes on side characters, building them up as their own protagonists, only to have Ains kill them off and never be mentioned again, essentially wasting the viewer's time and emotional investment.

2. Ains's (the protagonist) allies, the NPCs him and his friends created, constantly worship him. It was humorous at first, but after three seasons, this gets very, very grating. Some scenes are literally just stroking the ego of the main character, who is in actuality a huge turbo virgin who never leaves his house.

3. To use a video game term, being a shut in and doing nothing but leveling up and getting the best items, Ains is way too OP (overpowered). The show only gets its value by expounding upon the backstories of its side characters that exist within the video game, the ones that aren't Ains or the NPCs who serve him. His fights are somewhat boring, because again, they only serve to stroke the main character's ego.

3. Ains is wholeheartedly, unapologetically evil. Something went wrong when he was trapped in the game and he lost any humanity he had. Sometimes the show will build up a character's backstory for several episodes only to have Ains or his NPCs kill them brutally and anticlimactically. Or have them tortured and then killed. Or enslaved. The show does a good job to make sure you dislike its protagonist, and root for his enemies. Maybe that's by design, but it's not for me.