Shrink the character
After looking at the image I realise that the painting might feel more epic if the foreground character was smaller, to make the cliff and tree feel bigger. So I change the little ninja guy. I also tighten a lot of the lines and add some rim lights of sun peaking on the far peaks. I then introduce a lot more detail to the tree leaves and foreground hill.
I create a layer and set it to Linear Dodge (Add) mode. I then make a large Soft brush with the Flow setting set very low. As I paint it brightens the image and adds saturation where I want it. I can use it to add warm glow and bloom around the sunlight’s brightest area in the clouds and a bit more cool atmosphere, too. It’s also a nice way to achieve subtle colour variations.