As a new player of Paradise Killer: it's a great walking sim!
So I've heard some complaints about this game having not great assets, weird gameplay progression, not proofread text, etc. And since I'm a new player I don't have enough experience to disagree But the one complain that I absolutely can not agree with is the 3d exploration/movement being bad. It's perfect (at least for me)!
I don't know why, but it perfectly tickles my brain when I can explore a 3d space with platforming and exploration that is obviously non mandatory but with rewards to acknowledge the exploration. I love wandering around and jumping from rooftops to rooftops to find objects and talk to Shinji. I like how audio is used to tell you to look specifically, but it can't be fully relied on so exploring on your own is still worthwhile.
I don't know why, but slowly piecing together the lore and finding clearly marked collectibles and trying to do the occasional precise platforming is the best experience I could have in a game. I've barely talked to any characters, I've just been wandering around for 3 hours.