hey - im writing here after reading your post about colouring greyscale.. so im gonna comment on that..
i think the colouring looks a bit odd because you have a very saturated and intense red covering vast areas of landscape - yet there is no sign of that same colour in the other half of the picture. to sell the image as a whole it needs to feel more intergrated... ambient reds in the sky and landscape in the right half of the image and desaturated greys and purples in the left half..
after using colour overlays etc, i think its important to paint with these colours ontop of your painting.. touching it up. refining detail and correcting highlighst and shadows.
im bothered by the composition too - but cant quite put my finger on it.. its as if my eye doesnt know where to settle (although at 5am im struggling to explain this with any proper meaning! ) but i imagine if the colour was more consistent, this would help pull the entire piece together.

