Decent episode, all in all, but it could still have been better.
I was quite honestly appalled by how militaristic the Wonderbolts Academy's portrayal was, and how little questioning there was of the methods employed — none really, in fact. Having Spitfire as a drill sergeant also seemed rather out of character for her considering everything we've seen of her so far. (And how many Wonderbolts are there, anyway? I always thought that they were an elite team of flyers, not an army.)
Lightning Dust sort of reminded me of Gilda, not just due to her lack of caring later in the episode but also when she initially hooked up with Dashie. Obviously, unlike Gilda, she wasn't a heel; she may have been reckless and in need of learning a lesson, but she was still a likeable character all in all. I was glad to see that her and Dashie's competition remained friendly (between the two of them), and I hope they'll continue being friends. (Did she actually get thrown out of the Academy, BTW? I hope not; I think people have a right to make mistakes, although they also have a responsibility to learn from them.)
Regarding leaders/wingponies, I was dismayed that the message was apparently that "being a leader is a reward, being a wingpony is punishment, or at least proof you've not worked hard enough". In reality, all roles need to be filled to have an effective team; you can't have everyone be the leader, and filling YOUR role and doing your best is what matters: in a small and highly efficient team like the Wonderbolts where everyone needs to work together perfectly, primadonnas are absolutely the LAST thing you'll want. I thought that this was going to be the message that Dashie would learn, not "you've not worked as hard as your team partner, so you only get to play second fiddle — until you prove you're the better one after all, then we'll rip the leader badge off her and stick it onto you instead".
Nonetheless, the message about recklessness was well-received. And so was the slightly less explicit message: that it's important to stick up for what's right, and that unquestioning obedience to authority and blindly following orders, without concern for others, is not right. I'm glad that Dashie knew this and was willing to act on it, even to the point of having to leave the Academy — doubly so given how much she'd always wanted to be a Wonderbolt. (At the same time, this is a rather ironic message for such a militaristic episode, isn't it? I wonder if it was a very subtle form of criticism, or whether the contrast was unintentional.)
The bit with the rest of the Mane Six coming in in a balloon, plummeting to their deaths and barely being saved by Dashie's efforts felt a bit rushed (running out of time? I wonder if there was extra material there that was cut), and perhaps a bit forced as well: surely the destruction the tornado already wrecked should've been enough to get Lighting Dust and Dashie a stern talking-to from Spitfire. The scene was also rather similar to Rarity falling to her doom in Sonic Rainboom, which briefly made me think "...again?", but at least they resisted the temptation of having Dashie perform another one of those. :)
Speaking of the other Mane Six, I'm definitely growing more tired of Pinkie being written as nothing but a) quite literally crazy, and b) overly cartoonish. The occasional fourth-wall breaking is OK, but having her pull things out of hammerspace and fit herself into mailboxes and all that ALL the time, without anyone else even so much as commenting on it, threatens to turn the show from a something nominally realistic and slice-of-life-ish with witty fun (and morals driven home with an 18-wheeled big rig) into unadulterated and unabashed whackiness. And I think that's not what My Little Pony: Friendship is Magic is or where its strength lies.
At least I don't seem to be the only one thinking so, judging by Applejack's and Twilight's reactions to Pinkie's latest zaniness.
What else? Fluttershy's still having difficulties flying, it seems, the poor girl. Maybe it was just because she was so shocked, but OTOH you'd think that flying would be an instinctive reaction in pegasi. Either way, she was really cute when she was sheepish about it afterwards.
I enjoyed seeing Horse Power/Roid Rage/Snowflake again, too, and I was rather amused to see HIM accepted into the Academy of all ponies. (And judging by how she looked at his wings, so was Spitfire.)
I was also happy that while they ended the episode on a humorous note, they resisted the "everybody laughs" ending.
And I did like Spitfire's comment about how "it's not a race". Important lesson, that, in many ways: doing it right is better than doing it fast, and the goal of training is to become the best you can become, too, not to beat the other trainees.
So, all in all? Perhaps not my favorite episode, but hey, it's ponies, so I'm certainly not gonna complain! It's always nice to see more of them, and watching a new episode is always a highlight of the week. :)