Hi Maciek.
You dont have to be the best figure painter in the world to make nice dioramas, but as Claude pointed out, these could be improved by some simple shadowing and highlights to uniforms etc.
Personally, the scene looks very stiff and as everything is placed parallel to the edge of the base, it doesnīt help any. Donīt be afraid to cut away parts of the MiniArt buildings to angle them better and achieve a better composition. Having some guys playing cards in the middle of the road doesnīt make much sense either ... why not in the garden beside the house? The dio is not bad .. just can be better with more thought to the composition.