In a nutshell, things I've been saying for a while, here's the place to discuss them once and for all.
1.) I think Queen Chrysalis fell to her doom. There is no way she could have survived that, unless she's faster than Rainbow Dash or is immune to long falls. The comics depict her surviving, but it also showed the changelings landing in the same spot as her when clearly Chrysalis and her changelings were scattered in all directions and only one flew in the same direction as her. Besides, I want her to be dead for what she did to Twilight, and on account of how evil, malevolent, creepy, etc. she is, even though she's my favorite villain.
2.) As Meghan has said nothing on Chrysalis's fate you can think whatever you want with her, but King Sombra is 100% dead. Meghan confirmed that, and she shouldn't have had to given the way he shatters to pieces and Cadance said he wouldn't return. Only his horn (as well as him regenerating it earlier) gave that impression, so Meghan had to clear that up. Anything that suggests that Sombra survived came from people who aren't the show's creators; the only suggestions to Sombra's fate that the show or its creators have given say that he's dead.
3.) The writer of the Equestria Girls book mistook Spike's tail for his arm
4.) I think Lord Tirek is the grand finale for two-parter villains, because they can't top him in any way I can think of, or do a more epic battle than him unless they destroy him, which I think they want to avoid anymore after people tried to deny the deaths of Chrysalis and Sombra. Ironically enough, they wanted Tirek dead out of hate for him sending the princesses to Tartarus and destroying Twilight's library. So, if they ever do decide to do another villain (like Grogar, as many have speculated), if they have him do something the audience will hate him for, kill him, and if not, give him Tirek's fate, minus the cause for speculation/headcanons that he'll be eaten by Cerberus for sending princesses to Tartarus.
5.) The biting tails thing seems more pointless, and the fandom isn't what is used to be since the Alicorn Twilight rage (correct me if I'm wrong and people still respect others' opinions and interests here even if they disagree), but I'll just say it this last time: I think there'll be no more in Seasons 5 and above. It decreased dramatically in Season 3, and there was only more in Season 4 coz it's longer. It was an entertaining subtheme but they just don't seem to think of it as much, even Applejack only bites Rainbow Dash's tail once each in Seasons 2, 3, and 4, and Seasons 2 and 3 was hard to notice but Season 4 seems to have been intentional as a running gag, though Pinkie bites her tail more in Season 4.
I think this, along with the "no more villain deaths", seems to be the price for my wish of killing off Chrysalis and Sombra. But I don't care what they do next regarding villain defeats (unless it's karma houdini) or biting tails as long as Chrysalis and Sombra stay dead.
One more thing: This is an interesting subtheme to me, after how Applejack does this all the time (as well as one of my favorite shows being Dragonball Z which has a major subtheme of tails for the first half, including Goku biting Frieza's tail in Episode 74, which many would know as Episode 89). Another note: One guy seems to think biting tails is "fish fuel" (can't say the full name) for me but it isn't, at least not for the kind that saying refers to (and to the other, I wouldn't call myself "obsessed" either, if I'm obsessed with anything it's either villains' death scenes or The Other in The Avengers).
7.) Season 5 will likely begin in May 2015. They confirmed 2015, and there's been an increasing gap between seasons. Seasons 1 and 2 were four months apart, Seasons 2 and 3 were seven months apart, and Seasons 3 and 4 were nine months apart. So it makes sense Seasons 4 and 5 are a year apart, and the gap increases each time. People have argued this was because Equestria Girls came between Seasons 3 and 4, well guess what, there's Rainbow Rocks between the seasons.
8.) Not trying to sound like Abiru Kobushi here but why did the human ponies not gain tails in their transformations, as Demon Sunset Shimmer did? The clip-on pony tails they used in the cafeteria song looked more like actual tails than those hair extensions they got that simply looked like the ponies' tails. I understand they were probably trying to be cute with a "ponytail" pun but come on, they gained actual ears, and Twilight, Rainbow Dash, and Fluttershy got actual wings, so why not actual tails? Characters do more things with their tails in this show than in Dragonball Z itself (particularly Pinkie Pie) so why stop here? It also makes the song "Shake Your Tail" super-ironic since they don't have actual tails. If it were the clip-on tails it'd make sense but still, they should've used a song like that with the ponies, not the humans.
On that note, why didn't Twilight and Rarity get horns in the transformations either? Even Demon Sunset Shimmer didn't get a horn.
9.) The Nightmare Rarity arc of the comics is definitely non-canon. It depicts Nightmare Moon as being a dark entity from the moon (as opposed to the manifestation of Luna's jealousy, as the first episode said the bitterness in her heart transformed her into Nightmare Moon), and it shows her taking Rarity to the moon and convincing her to let her possess her, which is presumably the same thing that happens with Luna (as Luna implies "The Nightmare Forces knew what to say to convince me"). But in the show, we see Luna decide to move against Celestia, and when she does that, that's when her bitterness reaches its peak and transforms her into (or possesses her as, in my headcanon and as implied by Lauren Faust) Nightmare Moon. So she becomes Nightmare Moon before Celestia, not on the moon. Also, in the comic Nightmare Moon makes clear she is a completely separate entity from Luna and Rarity, but Twilight doesn't know this in Princess Twilight Sparkle, and apparently neither does Celestia.
Another note: I think King Sombra turned Luna into Nightmare Moon (obviously Tirek doesn't have that kind of power). When Celestia and Luna fought Sombra, he could sense Luna's resentment, so he cast a curse to magnify it, which gradually increased her bitterness until it drove her to try to overthrow Celestia, and by taking that final step, her jealousy and bitterness manifested into Nightmare Moon.
10.) On the subject of "Dark transformations or separate entities?", I think Demon Sunset Shimmer is the same as Nightmare Moon. The embodiment of her dark side manifested into a form of its own to possess her, except instead of jealousy and bitterness, it's cruelty for Sunset Shimmer, the cruelty that accumulated in her heart from her impatience, drawn out by the crown through her selfish ambitions for power, and once it was removed (by destroying her demon self), Sunset Shimmer turns good and, after witnessing what her demon form did (likely from the demon's point of view), she won't want to turn evil again. The demon remembers everything her other half did from her point of view, because she was once part of her. Compare Evil Buu, Majin Buu's evil side who talks of everything Majin Buu did from his point of view ("Each time I've annihilated a planet..."). Or vampires in Buffy the Vampire Slayer, though the process of transformation is considerably different.
11.) Chrysalis is dead
12.) There seems to be no pleasing the fandom. People like Chrysalis and Sombra so much (despite what Chrysalis did to Twilight and trying to make her kill Cadance) that they want them to survive their deaths in the show, and deny this to the point of some continuing to deny Sombra's death after it was confirmed, and one pegasister who writes for IDW bringing Chrysalis back at the first opportunity once Hasbro licensed IDW comics, which she did in the name of fanservice. Yet Tirek was clearly meant to outshine Chrysalis in every way imaginable except villain song, his battle is way more epic than hers, Sombra's, Demon Sunset Shimmer's, and Celestia vs. Nightmare Moon put together, yet people would have preferred if he was killed because of what he did to the princesses (all four of them). Although I guess their plan backfired by having him do something the fans would hate him for, but I guess they didn't think that was a factor since they didn't seem to mind Chrysalis turning Twilight's friends, brother, and mentor on her in the single most depressing moment of the show and trying to trick her into killing her foalsitter.
Also, why do so many people make a big deal about Sombra's death and wanting him to survive? As I recall the majority of the fandom declared him to be "lame" and "worst villain". I can't say I agree, he's my second favorite villain, he was inspired by Sauron, and they only hate him for lack of screentime and dialog, he's the most intelligent and competent villain in the show, he would have won if Spike hadn't gotten the Crystal Heart to Cadance (and if Shining Armor hadn't thrown her), also if he'd had a chance to do more he'd have killed Shining Armor, Cadance, Spike, and the Mane 6.
But I suppose you can't please everypony. A Canterlot Wedding was the last two-parter that did, but The Crystal Empire was the last two-parter that completely satisfied me, even though I like Twilight's Kingdom better than both because it has more things going for it, besides my one disappointment I can remedy with headcanon that Cerberus tore Tirek apart as punishment for sending the princesses to Tartarus, a nightmare dimension only Cerberus seems able to withstand
13.) For the reasons listed above in regards to the subject, I hope there's no more villain episodes. I liked the ones we got, even Princess Twilight Sparkle (Nightmare Moon and Discord's scenes made up for that lame villain that was the Plunderseeds, who themselves have a bit of redeeming value with the facehuggers), but they'll always disappoint somepony, unless they're somehow handled perfectly like A Canterlot Wedding, and there'll always be rage. "This villain is dead! I wanted her to survive!" "This villain is lame, he hardly has any screentime or dialog." "I wanted this villain dead, he did this to Twilight and put the other princesses through hell!" I myself am quite demanding when it comes to villain episodes, to the point of being disappointed if the villain isn't as great as its predecessors or doesn't get killed, but am much less demanding when it comes to the "slice of life" episodes, which tell an enjoyable story with characters we love without any need for a villain, and I can just love those episodes for what they are. So I hope it's just that in Seasons 5 and above, I'll miss the two-parters but we've still got six and they were good, even if some weren't perfect. Besides, the wait for villain episodes seems to take longer.
14.) Is Applejack a background pony now? This seems a matter of debate. On one hoof, she appears in more episodes than any of the other Mane 5, and is involved in all "Mane 6" episodes (fighting main villains, key to the box, etc.), as well as having some episodes of her own, or paired with others (as a matter of fact, of the other Mane 5, Applejack is the only one who's been paired with all four of the others in an episode revolving around her: Rarity, Rainbow Dash, Fluttershy, and Pinkie Pie.
On the other hoof, products seem to think of her as a background pony. When they finally released stickers for Friendship is Magic, they have all the Mane 6, Celestia, and Luna, but no Applejack. There are no Applejack toys at McDonalds, unlike the other Mane 5. And just recently I picked up a MLP poster at HMV which has all the Mane 6 except Applejack. I also remember someone pointed out a picture which has all the Mane 6, but Applejack is kinda blocked from view by the rest of them.
15.) I don't know but the fandom hasn't seemed the same since Alicorn Twilight, even though the rage for that has died down completely. At least most of the people who left the fandom are Celestia haters. (not that I hold anything against Celestia haters, you can all have your own opinions, but it was kind of annoying to hear them say they hate Celestia)
EDIT: However divided the fandom is, it's still 100 times more accepting than people who aren't in the fandom, since everyone on the Marvel Movies Wiki hates me for making so many comments about Thanos and The Other
Anyway, thanks for hearing me out and I'll try to keep my comments about these subjects on their articles to a minimum.