You already read this isekai story 100 times. The MC is your typical shonen MC, his goal is to be "the strongest in the world" (seriously ?), there's nothing special about him except that he's strong-willed and trains hard... Other characters are cliche and/or jerks. Art and translation are mediocre.
The 40 first chapters are the worst, it starts to be interesting at chapter 150 but IMO it's not worth it.

Pretty generic murim with pretty good execution, art is ass though

Quite entertaining. The writing is not the best and the character of the MC is not always consistent. I can see why it would be hard to write seriously a 40 year playing around with teenagers. This is still better written than most series in the genre.

The fights are quite well made. They do get pretty magical at later stages, but never to the level where they just become flashes of light and explosions and other nonsense where the reader can't tell what is going on or why it is happening, things are mostly comprehensible. A double jump is magical, but I get what it can and can't do and so on.

if before regression he rank around D rank, after regression he can reach A rank.. but not a S rank.
the system(quest) help him grow but he can't become OP because his

poor physique that limit his grow and that's kinda a killjoy for a system
and for a regressor with all that ! memories of past life trait, ke keep makes a mistake that can be avoided if he really have that trait. ! he only after something that takes place not before kinda insignificant trait if you ask me, well at least it's not worthless

Still super entertaining' if you like Shounen with cool fights, the MC is really nice and yea deus ex machina give him advantages... YET!! he deserve it with the sheer amount of hard work he puts into the training.

What is special is the characters and the intricacy of the trama and the world, which is not as banal as others. The characters are well written and the protagonist history is meaningful.
Classic level up, with some twist and a linear progression rather than exponential. It's still interesting at chapter 100+.

MC died then regressed to his youth. Found out that he is the only one has this so called system. He could level up, collect rewards, use space inventory, see people level and stats, etc etc you know what it is.
The dumbest part is his martial arts, where

he accidentally found a martial art book that let him use handle 10 weapons at the same time, gaining bonus stats just by touching a different type weapon, and spawning new arms out of nowhere

Art is great, story is great, MC is great, side characters are great. Hell, everything is great. Go read it now, you'll not regret it.

The story does a great job to balance the LitRPG game mechanics with real character development & strong ensemble.

The game mechanics are a lot of fun and definitely follow some of the tried and true tropes. Quests, leveling up, super powered rewards. They're also balanced so that the MC doesn't get OP in just one week. They're definitely getting noticed & making things happen, but it's reasonable growth rates. I think Tales of Demons and Gods is another good example of reasonable growth rates, but this is even better. Oh and definitely one of the best aspects of this is that the MC doesn't have a gaming background & has to discover how game mechanics work from scratch. Another fun element of the game mechanics is that the MC is smart enough to figure out hacks to some of the tasks while failing in others. Aaaand the game mechanics overlap with the normal world (so far) in a way that seems sensible.

On the character development and ensemble, SO many characters are getting meaningful back stories. And while the MC starts the story off reliving his previous life, there's a pretty good balance between how he punishes people for wrong doing in the past life vs this one. Actually, relative to the time rewind trope as a whole, this is one of the best managements of that. Tales of Demons & Gods is probably a little bit better, but it's definitely one of the best and hopefully they do a bit better as the series goes on. I can see a risk of it going badly though with the MC becoming some kind of god of judgement for people who have not yet made the mistakes he knows they would have made in his past life & getting post action justifications on a bunch of murders. Oh and the MCs main relationships have interesting storylines that are getting well built out.

So ya, all in all, I'm enjoying it! 🙂