Backing up what I say about feeling like FiM, it´s that the fic offers room to breathe within its development and let lines like these:
> "Are ya sure ya can't tell me what this Mare on the Mountain is?"
> "Mare in the Mountain, Apple Bloom," Sweetie Belle corrected.
> Apple Bloom rolled her eyes.
I personally see where this is coming and I can tell that this actually criticizes the constant spelling mistakes written in this board. Not only the sense of comedy is there but the CMC really show their characteristic tropes until the climax, meaning that the author actually acknowledges their personalities even if the story is going through muddy waters that could feel off if it was shown so directly to the reader.
So for the most part, this fanfic will sound familiar to the average fan but where the questions will begin from the start and the climax (not to mention the strange actions from Scootaloo and SB while walking to the place where Cadence appears). The philosophical questions aimed at Apple Bloom, the grim imagery constantly present in her mind and how Cadence goes even further by twisting an intimidating technique: reading the minds of other creatures. She doesn´t only change to a more questionable side of actions, she doesn´t only become a guide for Apple Bloom but she also displays a really creepy yet powerful weapon that she could have exploited in the past:
> Cadence let a light hearted chuckle that contrasted with the fearsome atmosphere.
> "Of course I can. How else do you think I fix, manipulate and twist ponies love lifes?"
Mind f*yay*king blown by reading this. As much as she sounds certainly out of place with those questions, she proves that her true potential and lack of fears towards the wrong things actually drive her to take a step forward, like she knows way more than in theory she should have in the first place.
The concept of her being a bat isn´t something that one would have explored al that much. This fic doesn´t jump right away to the center of her new feature like the original Cadencebat green did, but instead she receives almost a mystical presentation, wondering who she is and when one gets to her, there are far more questions than answers. There is always a haunting feeling that pays off with a mysterious climax (yet with dark imagery) and one could define it as mental edginess. Not a single moment of violence was brought onto the table yet those tense feelings manage to happen while reading this piece, like a horror movie that is slowly building up before murdering harshly the characters.
Overall, out of all the fics that you could expose to any gen 4 fan, this one has the right context/introduction, the familiar feelings to an extent and the characters properly written. We haven´t seen the CMC interacting with Cadence at all so the lack of presentations between them could make this fic pretty plausible for its concept.
The Revolution fic served for a cohesive yet an unfamiliar political piece, while The Mare in the Mountain has that, more lore and even dark implications to Cadence´s character. All of this by bringing original drawings by yourself and while they are not made to post on Derpibooru, one can get the imagery transmitted through those sentences.
If I had to pick one fanfic from yours and expose it to the public (/mlp/, FimFiction...), this one most likely would get praised from its consumers.
There you have it, you have written some proper original content that one fan would like to contribute to the fanbase.
Congratulations.