The Tutorial is Too Hard -- The setting for the story is a pretty typical dungeon climbing scenario, but the plot is heavily focused on the internal aspects of the MC as he grows. Isolation, loss, loneliness, fear, pain: all these aspects are explored and contribute to the protagonist's highly unbalanced psyche as well as his ridiculous growth. The way motivations make an alien sort of sense is what makes this story fascinating.

Everyone Else is a Returnee -- This story does not have any particular depth, it is just a fun journey of an antihero as he becomes the hope of the world.  Its charm is mostly in its wit and jokes. It contains quite a bit of referential humour though, so many of the references already feel dated. There are quite a few technical details that can be picked apart in this novel, but it is fun enough that none of that really matters.

I Alone Level Up (AKA Solo Leveling) -- This list is about novels with OP characters, but the novels have something else going for them. As such, this book almost didn't make the list, because it is a pretty typical level-up story. But what it does have going for it is good writing and a feeling of mystery that prevails through most of the book.

The Lazy Swordmaster -- The MC is the greatest swordmaster, but he pines for a lazy lifestyle. So the crux of the book is him going through great lengths to avoid being known as a swordmaster. Sadly, the translation got dropped at about 80%, and the original translator took this book down from his site, so you'll have to find it on an aggregator website .  On the other hand, the good part of the book is the first 67% or so, so you're not missing much if you can fill in a pretty generic ending.

The Legend of Sun Knight -- The MC is a crazy powerful mage/priest/necromancer/assassin (and probably a number of other class archetypes), but he has no talent for swordplay. Unfortunately, his job requires him to play out the role of the head of the holy knights.  The protagonist is constantly beset with issues both small (like a rival religion moving in on their headquarters) and large (like being unable to apply a mud mask for a whole week), and he must cleverly solve these problems in spite of being shackled with the job of Sun Knight. He can be a bit of a Marty Stu (except in the realm of swordplay), and it gives an unsettling life-is-cheap vibe, but don't let that keep you from this delightful story of politics, religion, intrigue, and hilarious double-speak.