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.
Anticlimax Boss: Although reaching him proves rather risky, much like in the show, Discord doesn't even try to fight back or stop Lyra when she and her new human friends use the Elements of Harmony on him, turning him into a statue with no fuss other than his screaming.
Fridge Horror: if Lyra had never found the books on humans, she would have grown up as being a normal unicorn for the rest of her life, with the probability of having foals and a special somepony. She would probably NEVER question her origin. And her human parents would have thought that their daughter was dead for the rest of their lives. And NO ONE except Celestia and Lyra's adoptive parents will know the truth.
Fridge Logic: Celestia knew that the baby human would probably never learn magic - turns her into an unicorn anyway.
Also, think for a while on what it would be like to have spent your entire life as a sentient horse, only to learn you've just eaten the remains of another hoofed mammal.
Strawman Has a Point: Bon Bon can come across as frustrated and sarcastic, and we should see her as an insufferable skeptic, but she makes some fairly decent points: Lyra hasn't any real proof besides some books and dreams, something Twilight agrees with, her behavior is shown to be weird by the description of strangers, and Lyra needs to improve her image to advance her career, with Rarity agrees with, and her limit is pushed by the fact that Lyra nearly hurt somepony with the cart she brought to life. Of course when Lyra comes back to Equestria with not only proof of humanity, but the fact that she herself is human all that is left is her sarcasm and frustration.