As for Bookworm, it really really sucks how it started going, because part 1 is so strong and different. The series is almost and edutainment story with how it goes over the details of how books have been made throughout history, paper, ink, the printing press, it goes into a lot of detail on those things and, unusual for me, but I liked the low magic setting it initially starts with. It also had real world, realistic problems, I loved the orphanage plot line because it threw cold, harsh reality at Myne with the problem she was faced with and it wasn't something solved easily or with magic or anything.Spider shit the bed so hard on the adaptation, by the end there's barely any animation, I'd hard skip unless someone is desperate for more isekai. The manga is much better anyway (cut out all the generic human side). Even then its not worth reading on after the labyrinth arc, it might as well be a different story.
Overlord also really struggle in adaptation quality, S2 was really bad and apparently S3 is worst.
I like bookworm in concept, but execution is mized. The main character is incredibly inconsistent and constantly give up over the smallest set back (often caused by her own stupidity). And around halfway point of S2 it gives up most of its premise for "the main character is the most awesome things in existence" stuff.
The only serious isekai (ie not konosuba) that I liked was grimgar, but its so different from most isekai that it makes little sense to call it as such. The character are all very weak and there's not even an hint of harem or slave girl. But it deal with loss in a pretty serious way and character action have consequence.
But Part 2 is when it just seemed to lose itself. It turned almost all the characters from part 1 into side characters, it stops focussing on Myne's goal of making books, Myne starts solving her problems easily and often with magic, people start inexplicably liking her at the drop of a hat whereas before she had to struggle to earn the trust of others. And it makes the character Ferdinand a second protagonist and that character encapsulates the most pervasive aspect of isekai which is hyper competent and over powered main characters with how he's capable of anything and basically runs the entire city by himself. Ugh, I fucking hate that character. Such a disappointment for me.