The first thing I'd like to comment on is the ingenuity of Cloudsdale. not only have you captured the magnificence of such a city, but you created it from your own perspective and given it a breath of life. It looks less like a floating city and more like a kingdom in the sky. The shading gives it a feel that sets it apart from the rest of the sky but makes it fit in just perfectly. The sense of perspective is really made whole by Rainbow Dash, who also looks expertly drawn, giving off a sense of pastel realism. The attention to detail in the background is astonishing, considering the piece is meant to attract attention to the pony and city. the clouds, the faint rainbows beneath Cloudsdale, and the landscape give it a full sense of completeness that, without the perfect touches you've given it, would keep this picture seeming to have that 'something that'snot quite right' about it. Every aspect contributes, rather than distracts or overpowers the other parts. I'm truly amazed at the quality of this, and how much effort must have been put into the development of something like this.
I gotta say, I love that framing! Nice placement for RD and Cloudsdale! Personal favorite part about this piece are the light rays and the shading on the city itself. Bravo!
Above all else, I'm really just digging the epicness and scale of it. As soon as I saw it, I was reminded of the opening notes to "A Bug's Life" ([link]). It gave me this vivid image of RD flying through the clouds. She finally pushes through a thick section just as the music crescendoes, and this painting is that moment. Magnificent! :3