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: Bitter Sweet
Les Yay: Hinted at in the main story. The final part before the epilogue has some Pinkie Pie/Rainbow Dash hints. It's also implied very heavily in the alternate ending.
Fridge Horror: Mixed with Harsher in Hindsight. The absence of Pinkie Pie affects the entire town of Ponyville so much that one is willing to break the laws of nature to revive her just so that Ponyville will be back to normal... And if her being absent and working at Sweet Apple Acres that one time had caused everyone to break out into fights, imagine what would have happened if she died.