The Red Baron
I find it interesting to mix elements from history and pop culture that are rarely found together. I rarely see classical fantasy tropes like dragons meeting settings taking place in modern times like the first world war.
The real Baron von Richthofen never lived long enough to see himself become an older Gentleman with a gray mustache. Maybe I was thinking of the character of Baron Münchhausen when drawing this picture, which would fit the fantasy scenario well.
This might be interesting for you as well:
On of the roles of the composition of an image is to depict the most important elements of the picture in a clear, recognizable manner. For color pictures, not only the placement of the elements is playing a central role, but the color composition as well.
An obvious method is to separate diffrent elements or layers within the image like foreground and background by different color saturations of a difference in lightness.
There are many approaches for setting up a color composition. To acquire some helpful rules of thumb, it can be useful to look at some of the oldest works of visual design in history: Coat of arms and flags.