I've put more hours into the game. It's a mixed bag.
The main story seems interesting until now. I'm not sure how much it fits with the Cthulhu mythology but it's pretty atmospheric.
I'm like 3 main quests into the game and they are long but it looks like the game has a main story and all the detective quests have no impact over that overarching story.
But this is not a proper open world game. Almost 20 years after Gothic these guys still don't know how to implement a proper open world.
1) Many quests locations are available for "visit-only" meaning that you can visit them but the quest triggers are not enabled which means that
it makes absolutely no sense visiting locations for which you don't have a quest assigned. Fuck exploration.
2) Quest sequence breaking ist verboten. I had one of the most annoying experience when I had to search a specific store in an area. I combed the entire area but the door was enabled only once I went to the City Hall and searched for that specific company. Fuck exploration.
3) The town is lifeless and the NPCs have no schedules. I don't know why the fuck they bothered with the open-world implementation (it doesn't matter if the world is dead) except as a tool to waste the players time. Fuck exploration.
4) The world map is simply atrocious because it's a puzzle

It doesn't make sense geographically or topologically. It's just a mess that you have to navigate. Fuck exploration.
The combat is another can of shit: almost all combat mechanics are broken, clunky or unresponsive. I cannot prepare for encounters because when combat starts I'm fighting with the controls and the camera instead of the monsters. It's luck based gameplay
And the cherry on top of the shitcake is the broken save system: you can save anytime but the game will not save your actual position or the quest current state therefore on reload you will spawn in some predefined phonebooth but also quest items will respawn. This can be exploited in two ways:
1) go to a new area, die and get respawned into the closest phonebooth ... it's much faster than searching each phonebooth,
2) go to the quest location, loot stuff, save, reload, go to the quest location, loot stuff, save, reload ... you can do this a lot if you don't ever finish the quest sequence.
Honestly, this is one of those game where you feel like swimming in shit because you know there is a good a game somewhere below the surface but my God! you have to work for it.