These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: My Little Pony Friendship Is Magic S 3 E 9 Apple Family Reunion
Fridge Brilliance: Why is a character as energetic and loud as Braeburn nearly silent? In almost every scene he's in, he's carrying something in his mouth.
Fridge Logic: According to Apple Bloom, every member of the Apple family will be attending, including Babs. Which should mean that Babs' parents should also be there, though nothing directly alludes to them, and when Babs is leaving she seems to be travelling by herself. This begs the question if they are still alive (which would explain a lot about her bullying issues from "One Bad Apple"); alternatively, this would set up Aunt and Uncle Orange perfectly as Babs' parents, which is consistent with everything else we know about the Apples to date.
The song features a Palette Swap of Octavia playing the fiddle (Since named "Fiddlesticks" by the fandom). Given the fandom's tendancy to latch on to characters like this and the fact she got almost as much focus as DJ-PON3, only time will tell whether she will become this.
So Okay, It's Average: Seems to be the consensus, due to the episode's focus around Applejack, with no scene stealing characters or particularly memorable gags in sight.