Nice, cool, well done, unique in its category... i could continue but i don't have enough time and battery on laptop to do it XD
The clouds, the sky and the sun are very nice; the expression on both dragons, shadows and the light through the wings are really worked (i think your hand and eyes are very tired of all time you've spend in front of screen XD)
Do whatever your heart dicts you is the best and take this critique as an advice. In my opinion, if flay's tail shines, its light should cross the cloud and let us see it well.
Anyway, it's really nice, still in this way, or improve it ^^
totally "yes" about the eyes...
I guess its my best bg pic so far...
About the tail and clouds: sun is also making a lot of light,and Flay's glow is less visible on light,and still cloud is reflecting sun light making it more Shining...
So I guess its not really nessesary there