Great start and I hope you keep working on this.
Atmosphere hits exactly the way it should, the models and art are a good fit even if they need some polish, and navigating a difficult map and environment while managing resources is the perfect way to adapt the series.
The procedural generated blocks and different paths to the tower is more than I expected from this but I think that's also the clearest place where you can expand. More blocks that can be generated, even really simple ones, and tweaks and variation to the present ones can go a lot to make the repetitions less noticeable and give a really new city to explore each time you load.
Some other small suggestions: Having to carry boxes back to the kettenkrad instead of them just being sucked into your inventory is just a bit of intentional clunkiness that would make the survival feel deeper and more immersive. In a similar vein I think the kettenkrad feels just a bit too smooth and quick when driving it. Finally I love Owari no Uta but it always playing is a bit much, adding a rotation of songs or having the radio just turn on randomly like it does in the show would be a great small change.
Sorry if this was a bit long but this project is amazing and I've wanted to see something like it for years. My expectations are already surpassed, keep it up!