Indeed Sytse,
the planes are all very brigth comapred to the dark and dominating ground. That makes it quite a bit unpleasing to look at. The eye has no real starting point or course to be led through the composition. It'S almost like the object are plastered everywhere, especially as everythign points into different directions. I suppose the Eagle is the main object in the image, so why is it put in the bottom left corner then? Kinda distracting. Having the image object off center is a good thing generally as placing objects in the very middle could kill all movement in an image and make it boring but i think it's too much movement here
So much for my 2cents worth. Hope it doesn'T sound harsh but afaik if it's asked for personal opinions and they should be given with all honesty. Hats off mate!