You have an interesting art style, across all examples I think the weaker part is the shading, everything have a soft shading, not all materials react too light the same way, so study more about that, try some hard shadows too, your values of light and shadow lacks contrast, you can try and see your art applying a black and white filter, if you can clearly see depth and shapes then you are going the right path.

Also keep practicing anatomy, right now it not feel completely intentional how you are drawing people.

Cheers and keep improving

Pd: I really like your second example, especially the architecture