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 S4 E7 "Bats!"
Broken Base: Was Applejack in the right for wanting to stop the bats or was Fluttershy right for wanting to find an alternate route? Fans seem split on either option, especially since that plot point was quickly dropped in favor of a potentially better one. Fans are split on that as well, half wanting to see that plot be fully developed while the other would rather they do the Flutterbat plot.
This comic, posted soon after the season 3 finale.
There's also Nosflutteratu which was posted a year before the episode aired to the day.
An episode made for Halloween that premieres around Christmas, which has a song that pays tribute to Danny Elfman. Hmmm...
The giant apple, previously seen in the parody Equestria Girls videos.
Informed Wrongness: Applejack. While she agrees with Fluttershy in the end, her initial position, that keeping the bats around risks destroying the farm, is an entirely valid argument. As seen below in Strawman Has a Point, Fluttershy's plan doesn't really address the problem at hand, yet AJ is treated as being in the wrong for not initially going along with it.
Rewatch Bonus: You might miss it the first time, but Fluttershy's cutie mark changes to bats when she's a vampire.
They Wasted a Perfectly Good Plot: The episode could have easily focused entirely on the conflict of Applejack wanting to get rid of the vampire fruit bats vs. Fluttershy trying to find a more humane approach to the situation. Yet, given how everyone else pretty much sides with Applejack's idea (not to mention the hand wave to explain where the rest of the Apple Family was during the episode), it feels like "vampire fruit bats invading Sweet Apple Acres" plot point was only there to serve as a set up for turning Fluttershy into a vampire.
Wangst: Fluttershy's constant complaining about using the Stare can come across as such, since she was never shown to be this reluctant about doing so, and as noted above, comparable things have been done in earlier episodes without her batting an eyelid.
What Do You Mean, It's Not Political?: With the debates about the species’ drawbacks and benefits for the farm’s economy, Fluttershy’s communication issues with the bats, and the general rhetoric used in the debate, one could think they were discussing the issue of immigration instead.
Harsher in Hindsight: If you believe in the political subtext, considering the bats as parallel to immigrants, Rarity's line about "These vermin must be stamped right out" is this trope Up to Eleven.