Nice, always good to experiment.
Perspective looks a bit flat on these. Note for example on the windmill one, you have three very clear indications of perspective for a vanishing point under the mountain in the diatance: the trees and the circles that make up the windmill. For the trees, as they are arranged in a file towards the vanishing point, each tree gets shorter and smaller and closer to the next, and for the windmill each circle or ellipse is angled more or less based on how much higher or lower it is with respect to our eye level or horizon line (you can easily make them by making four-sided planes based on the vanishing point and draw the ellipses inside them
Cheers