It was pretty good, funny at times, and quite exciting during fights.
However, the next case after the tomb murder case was quite boring (it starts chapter 452), because there was no link to the original story. It felt as if it were just a new investigation unrelated to the plot or the other characters, which isn't interesting to follow.
Author introduced two people mc helped, one almost suicided, the other one almost got raped, then author left them out of the picture, and then he randomly killed them for no reason (killed chapter 494).
As luck would have it (lol), the killer even brought up a clue as how to solve the previously boring case.
I've let it go in the past, as his system makes mc luckier than usual, but here I can't let it go. Why TF would you introduce two characters we should feel empathetic about, not use them for a while and straight up kill them when they pop back up ? We don't know them enough to understand who could have killed them and why, why did author think it wasn't going to get very confusing ? Just to actually wipe them out to only bring a clue to the f*cking boring case from before ? Which ending we could see from a mile away ?
We could also somewhat see the ending of most other cases coming but it was done well enough that the feeling was still good, here it's extremely bad.
You created all those interesting female characters, why did you stop using them ? You couldn't think of other scenarios, so you had to introduce other disposable pity relief + angry inducing characters just to create a new short-lived intrigue ? Trash thinking and standards for a story.
The side quests from the system were quite a good and refreshing idea to deepen the settings and plots, but you just used it as an emotion spike for the reader, truly a waste of energy and of a previously nice story.