But problems soon arise that show that expectation was good in theory, but in practice...not so much.
But first, Twilight gets to do something princess-y! And, better still, there actually IS a community in Equestria that cares about Twilight being a princess now! Actually, on that subject, I figure Equestria care a lot more than is commonly portrayed. It's just Twilight has hardly ever been shown outside of Ponyville this season, and so doesn't get out where the ponies who would say they care would be around TO say so. The Ponyvillians don't react much, because for one, they already know Twilight, and two, Twilight has made it clear (and did so again in this episode, so you can't deny it) that she REALLY doesn't like the special treatment that comes with being a princess and is quick to discourage it. And since she's always in Ponyville, the Ponyvillians learned quickly and have largely opted to respect Twilight's wishes, or so my justifications on the matter goes. Pretty much the lack of attention Twilight gets for being a princess now for the whole season.
The only exception would obviously be "Rarity Takes Manehatten," but I argue storyteller's prerogative there; Twilight and her princesshood was not key to the story that didn't even focus on Twilight anyway, and thus was overlooked so to spare time to give the true tale adequate focus (and since that episode turned out so well, I say it paid off).
Of course, maybe the Manehattenites really don't care if Twilight is a princess or not. It's Manehatten, after all.
Anyway, this was one of those episode where the writers send the Mane 6 off somewhere and let the characters tell their own story, to see what these characters will get themselves into. And in the end it all pays off in terms of writing, because though few of the characters actually got what they had hoped to get from the trade exchange, they all learned something more important out of it.
Rainbow and Fluttershy, the storyarc of greatest focus, learned that friendship is more important than any physical item (even one you bend over backwards trying to get), Rainbow more than Fluttershy. Rarity and Applejack learned much the same, but in a different way, as they both sacrificed what they really wanted to get so the other friend wouldn't have to miss out. Because of it, they wound up having to settle for something less, but their friendship remains intact and if anything, strengthened. Twilight learns that just because something isn't really needed anymore, it can still have sentimental value, and that has true worth to it too. Pinkie and Spike are perhaps the only two characters present that didn't seem to gain all that much out of it, though I suppose Pinkie learned that one shouldn't put your expectations too high for something, otherwise you'll never meet it (and will likely backfire on you) and maybe that Twilight is more than capable of handling her own trades herself (even though she ended up not trading anything in the end).
Spike just lucked out and ended up falling off the side of the episode in the end, but at least he's shown have gotten something he wanted out of the trade (though we never really learn what. I assume it's some mint comic, but I would've liked to know, if only for curiosity's sake).
Aw, but it was an episode you walk away from feeling very satisfied and a little moved even by getting to see these bunch of ponies continue to learn and grow in various ways and continue to strengthen their friendship. Best of all, they walked out of it happy and satisfied at the end of the day and that's what matters. Hopefully you, the viewer, did too.
Apparently Discord-shaped lamps are a thing now in Equestria. I suspect Discord is somehow involved with this. Don't know what makes me think that... *wink*
Maybe that's how Discord passes his time now that he's been reformed; making lamps in his own image. It's constructive at least, if that's really the case.