Good start, but unfortunately dull open world and only arena fights are lacking a lot. I like the whole approach and creativity, but it just falls short. In the end, I think NMH1 as a playthrough is enough.

In the end, game 3, was overly cringey (french cook) and does not hold up, and was quite a drag and so long. The cases got more complicated in a way it doesn‘t make fun anymore

It‘s the weakest of the Mullins Games and may just be an addition to the whole universe canon. But gameplay wise it‘s boring, as each individual game is only barebones of it‘s genre and nothing special.
There is also no revelation like Inscryption does so right and even Pony Island.
It's a mixed bag of all sorts of genres, but basically just a walking simulator.