The character designs and imagery are fine. Since the novel rarely had detailed character descriptions, there wasn't much to expect design wise. There are two problems I see that don't relate to the imagery.
The first big problem I see is the translation. Just by comparing the first chapter of this to the novel makes it clear the translator isn't trying to make it accurate. An adaptation should have similar terms to the source material, but there are so many translation differences that it's clear they don't care. An example would be Essence Energy Art versus Qi Spell. Essence Energy is the name used for energy throughout the entire novel, so Qi should not be mentioned here. As for Spell, I have no clue why that's used instead of art. This whole ordeal just makes it more confusing for people who want to read the original work after reading the comic.
The other big problem is the story development. Just chapter 1 alone covers 3 chapters in the novel. The end of chapter 1 corresponds to the end of novel chapter 3. One might expect a decent bit of content from those 3 chapters, but in fact, a lot is cut. One very important detail is the information about how dimensional crystals usually work. That being one needs to absorb crystals of higher values to increase stats. By leaving just that information out, people are left wondering things like "why are his stats so low?" or "is he bad at the game?". Since dimensional crystals are one of the items seen very often in the story, they shouldn't have cut information about the simplest aspects. By hiding this information, people have less of an understanding of WHY things in the story are important or special.
TLDR: This manhua is trying to rush through the story without trying to make a faithful adaptation.
