Hello there! I like the mood of the scene and mostly agree in what Liz just said. But let me add a little more.
I think your image would profit a lot from atmospheric perspective. I'm sure you've experienced yourself that the further things are from you the less saturated and more blue tinted they get. It is because the light has to travel through much more air particles from those far away objects to your eyes. But I don't want to go into the physics of this phenomenon.
What I want to say that your painting lacks depths. I can't feel the distance of the mountains the burning village, etc. With a little atmospheric perspective you can solve this problem. See my quick overpaint below (I hope you don't mind)
One more thing. Pay attention to values! On your original piece the dark tones are all over the place which makes hard for the viewer to find a focus point. Usually the things closest to us are more colorful, and darker in tone, than objects further away. I'd suggest to keep the riders, especially the closer one, the darkest parts of the image (keep them as they are right now) and lighten up everything else.
Bonus comment: The overall color palette is nice, but maybe you could add a little (really just a little) more saturated colors on the characters. Their capes perhaps. To spice it up and enforce the focus even more.
Keep up the good work!