Week 11 - Landscapes - Colour

This is my drawing for week 11 on the topic of basic colours in drawing. The drawing took just over an hour and a half and it was done at late morning (around 8-9 am). Weather was dull (as usual), so there are no strong highlights or shadows. Since the sun wasn't visible at all, there are hardly any shadows visible.
In terms of compositing, this time I decided to experiment and try putting the drawing in a implied frame. This is the reason for the curtain on the far right to be present in the frame. The table being cut in the bottom left corner was also supposed to be a framing element along with the tree at the left edge of the image.
Rule of thirds has been used to position the mid-ground ground level and the deepest point of the image (on the right of the yellow-ish building).
In terms of colour usage - I didn't get a lot of opportunities to mix colours apart from the trees, the grass and the grey-ish path in the foreground. The grey path also shows a subtle shadow from the brown building on the right, speaking for a light that's coming from the right and in front of the viewing point.  The table on the far-left shows the reflected sky in the horizontal flat areas.
The image also seems to lack enough shading - the curtain and the small grey building in the bottom-right rule-of-thirds point need to be darker.