For technique, I love your style! It looks like the show, yet realistic enough to be original and set it apart from all the boring flat-colored pieces that try so hard to be exactly like the show. The expressions are spot-on, Twilight looks so hilariously frustrated, and Fluttershy's innocent smile makes me giggle.
But my absolute favorite part is the little spots of light on the grass and the trunk of the tree. I don't know why, but it's the little subconscious effects like that that make this piece such a hit with me. You really did a great job there!
Alright, now to the nitpicky stuff. I gave vision four stars just because the colors could be a little more saturated. Maybe it's just my taste, but having Fluttershy's mane and tail, and Twilight's for that matter, be a little more bright and candy-colored would make the piece more appealing.
Those things aside, I'm going to wrap things up with saying that the background and detail work is truly amazing. The detail on the forest is exceptional given that it's a background, and most artists spend little to no time on backgrounds. That's true for me as well, I'll have to work on that. And the sky... wow! I can never seem to get clouds right, and you nailed it! I may actually have learned a thing or two from this that I'll probably use in my own art someday.
So, in short, I think I have a new favorite! Definitely keeping this in my faves to look at from time to time. It really is a masterpiece.
Why do birds suddenly appear
Every time you are near?
Just like me, they long to be
Close to you
It's so cute!