I loved the episode, and the character growth for Rainbow Dash. We've been waiting for this story since the pilot and it went roughly how I expected it too.
The conclusion was short and could have been given a little longer to really do it properly but then 22 minutes leaves little room as we've seen plenty of times before.
Pinkie's abandonment issues from Party of One resurface but luckily not enough for her to go full Pinkamena but it was nice to see them tackle that again.
Spitfire has always been the Captain of the Wonderbolts, who as Gep pointed out are a semi-military squadron for Canterlot. We know next to nothing about her and always off-duty. She wasn't all that hard to believe this week, and the ending showed us the Spitfire we know when she loosened up a bit, so it's still her.
Nice way for them to include the mane6, very similar to their arrival in Sonic Rainboom and for essentially the same reason again. And just like that episode Rarity needs saving...
I loved the moment when Fluttershy, having been rescued, starts flying off and cue a very pissed off Flitter with her "why didn't you do that in the first place" expression.
But Lightening Dust...wow, borderline homicide of 5 other ponies, doesn't care in the slightest? we've had some real asshole antagonists in this show but a normal pony with that level of sociopathy? that's cold.
For now we know RD is a team captain, not officially accepted as a Wonderbolt so it leaves the door open for resolving that later.
But it does leave a serious question for the series as a whole. The promo's, and the production staff, go on about "a pony discovering her true destiny.".
Well, we have the leaked image showing a return to the Crystal Empire that has not happened yet that could still revisit the "Crystal Princess" line about Cadance, Rainbow Dash still not technically becoming a Wonderbolt and all the fore shadowing of something important in Twilight's future, but which one is it?