I think that the painting is missing something, like a tiny warrior, going towards the castle. or a dragon, flying somewhere in the mist.. which one fits better? or maybe someone could suggest me what to paint in?
I think what fits better is any element you like to put in this work. The painting has a beatiful idea behind it and great basis to continue. You should make it more realistic. Perhaps a waterfall somewhere near that castle or something like that. Anyway, I don't think you finished it.
I know this is a year late, but I love this one. And as for what to add that isn't too generic; how about flags blowing in the wind along the slope or samurai with long flowing sleeves (a la House of Flying Daggers). The mist and fog shows nice motion, but colorful showing motion would stand out. It's hard to say with the scale of the image though. Anyway, fantastic.