>>/12191/
> The were in-jokes that flew over the heads of 90+% of the audience.
They certainly went over my head!
> Yeah, one thing that I did dislike about the episode--and it was a complaint that I had about several Season 1 episodes--was how utterly frustrating Fluttershy often was. Just say something instead of dragging the story on by being a wimp
I think I've come to appreciate more the balance the show had with the mane 6 in their paired up episodes, trying to be evenhanded - because I would side much more with Fluttershy in this episode and it was Rarity I found annoying. So really, the episode had to be fair to both otherwise one side of the viewers would end up feeling alienated, I think. 
 >>/12192/
> It would figure if Faust, Gen 1 fangirl that she is, retained some of that early-80s brutality.
From her other work I think she also understood why that brutality was present to begin with - there's few tools as powerful as juxtaposition to illustrate your themes, and having the dangers present in both g1 and g4 make the fun, innocent moments all the more safe and cozy. It's the same principle as snuggling next to a warm fire during a storm: you could do it on any night, but the wind and rain make it cozier. 
 >>/12193/
> You have this city on terraces attached to the side of a mountain, and most of its residents cannot fly. 
I was actually thinking more from the perspective of how Canterlot is more modern and cosmopolitan (but in a good way) and so more likely to have ziplining hobby-type areas, but that idea works too!
> Apart from just shamelessly ripping off Olympus from Disney's Hercules, that is.
I would posit that Cloudsdale looks Greek because the Pegasus is a figure of Greek legend - iirc, the Pegasus rises from out of the fallen corpse of Medusa? Regardless, it's part of classical Greek mythological canon, so the same origin point as Olympus - and since Olympus is the home of Gods who are Greek, a Greek flair to cloudy architecture naturally makes sense for any Olympian-type imagery, not just the movie Hercules - though I do quite like that movie's take on aspects of Greek myth!
 >>/12206/
> You know, I wouldn't have gotten my cutie mark if it weren't for her. C'mon, she'd have to go to the ground at one point if it was her natural talent and place in life, right? 
It is a character's statement, so it could reflect a mistaken belief about how cutie marks work - I don't know if even during the later seasons we ever got an answer to whether adult ponies without cutie marks exist or not. I also wonder whether cutie marks preexisted the advent of Harmony with the first Hearth's Warming - if cutie marks are a function of Harmony, then like Harmony itself they're malleable rather than tied to a deterministic idea of fate, and I would assume your cutie mark would vary based on the talent that best suits the path one is going down and the most opportune time for you to discover it. I'm not so married to that theory that I'd be upset to see it proven wrong, though.
 >>/12207/
> I don't know if it was intended to resemble a flag or if it was just something born out of the limitation of their medium/chosen art style(let's make Celestia be in a silhouette! Solid flat color with no shading or gradient that gives shape to her). 
I'd assume it's meant to look like it's being presented as something like a symbol or a flag, since the stage deliberately frames Celestia to be silhouetted against the sun relative to the audience.