That's some criminally low rating! For what it is - it is an amazing Konosuba parody, with unique ideas for events. A lot of great animations, and i'm not talking only about hentai scenes, game utilizes animations quite well even without it. Writing made me enjoy the game a lot, too, i even treated the game as if it's Konosuba story, instead of some hentai game to fap on.
The usual complaints from people are Kazuma not being Kazuma, difficulties with understanding what to do, NTR guy not fitting in, and map design being garbage... and only two of those are a real problem. Kazuma being completely different is an intentional design, after all. He also gets a lot closer to acting like Kazuma later.
Battles are fine, maps are moderate. Kazuma is supposed to be cunning, and it seems it's expected of you too. For example - you should absolutely utilize Aqua to annihilate mobs and get yourself to a high level. Unless you use Aqua for that, mobs will delete you, or it will simply take an eternity or two. At some point battles will be solved automatically, as long as Kazuma's health is high enough, and it drains about 15% each autobattle. Battles also might seem like a non-issue in the plains, but second location has WAY too many cramped enemies, so getting your level high with Aqua is unavoidable. Bosses are funny too, you have to solve them, it's never a default RPG maker boss fight.
Now about confusion, i personally see no problem here, as it's needed for NTR. The dark rooms are RNG with what companion you'll get, and it's for a good reason - if you could get all of them consistently, you would have zero reason to extend your time to the 30 days limit. After all, they're all gimmicky, useful to solve situations, and if you get, say we, Megumin first, to blow up the boss, Aqua second, to level up, then gather the stuff alone easily, and then Aqua and Darkness to destroy the cave, you'll end the first chapter way too early. You HAVE a way to solve this and get them all when needed, but not right away. You'll also miss some scenes with heroines if you go too fast. Don't panic, take your time. For me i ended the chapter on day 8, and black guy only got a titjob from a side character.
From what i've seen, hentai is good, but... you wouldn't really see a lot in the first chapter, if you're playing the game right. Though i would say hentai games are more than just a fapping tool - it's games with perverse atmosphere, a certain lean you wouldn't get from normal games, so it still works as one.
NTR guy feels as if a default rpg maker NTR villain invaded Konosuba, got isekai-ed into it, if you will, and Konosuba cast plays against him. Nothing more, nothing less, a no-name buff black guy that exists as a meta-entity of netorare. Felt good to have them win over a universal evil like that.
That dark Labyrinth is way too torturous though. For making me navigate it i would've dropped rating from 5 to 4. Like, wtf man...