I also found probably the most important clue in the game Witness and Carmilla’s secret room by accident which kind of sucks. But I think the big issue is that it wasn’t well hidden enough.
Removing the collectibles wouldn’t make Paradise Killer better, because the island would be too large and empty, and traversal would become a real chore. You’d have to reduce the map but then the island would look unimpressive and why even have a 3D world at its point. The logical conclusion would be to either make Phoenix Wright (no 3D world at all) or Dang old Grandpa (very small closed spaces, and optionally a world map) again.
I agree that the investigation and 3D exploring parts are completely at odds with one another but I wouldn’t say it’s necessarily a bad thing. The approach is similar to the Zero escape series, with clear separations between plot events and puzzle rooms, both being entirely unrelated but bouncing off each other nicely and allowing the game to breathe. Paradise Killer improves on that formula by giving more leeway to the player in terms of just how much investigation and how much 3D exploration they want to do and when
Anyway I got further in and got completely enraptured by the world, characters, style and music. Favourite track:
Honestly this is going to end up as my favorite game of 2020 which is pretty ridiculous considering I have no interest in vaporwave and only found out about this game by randomly browsing the switch e-shop