Some headcanon for you... · 2:37am Oct 18th, 2019
These are ideas I've kicked around, but I'm not attached enough to any of them to want to argue about them. Pick a fight elsewhere.
The world where MLP:FIM takes place (Earth-P) is a rogue planet. It doesn't orbit a star, but instead is kept warm by a small, artificial sun. (Small relative to the planet. It's still really, really big.) The sun was made using a combination of magic and science, both at levels far beyond what ponies are capable of at this time. Earth-P's moon may be artificial as well.
The world of Equestria Girls (Earth-EG) does not exist in a true alternate universe; instead, it's an "echo" of Earth-P. What's more, it didn't even exist until Sunset Shimmer went through the portal for the very first time. As for the sirens, they were in a sort of stasis until the world became available to them. Why does the portal work fully for ponies and not for sirens? Because it was meant for ponies. It was to provide ponies a look at what life was like once upon a time for their creators -- the humans who engineered magical ponies and other fantasy races to populate Earth-P.
Twilight Sparkle, Sunset Shimmer, and Starlight Glimmer are all VERY distantly related -- their common ancestor lived about a thousand years ago and was a trusted unicorn advisor to Princess Celestia after the Nightmare Moon incident.
Prior to her ascension to alicorn status, Twilight Sparkle was very likely the unicorn with the most raw power in Equestria -- and her level of technical expertise with magic just made her that much more dangerous. As impressive as she is on the technical side, though, Starlight Glimmer is actually better. (Which shows what you can accomplish when you're determined, angry at the world, and learning at your own pace.)
The Crystal Empire was once much larger than the small city-state it has become. Other towns and villges are now frozen under thick layers of ice, either due to a thousand years of neglect in the frozen north, windigos responding to Sombra's bad mojo, or a combination of both. It was fully indpendent before Sombra's reign, but these days is a protectorate of Equestria.
A lot of what's in the MLP comics is canonical (in my view), but I'm not sure I'm completely on board with King Sombra being yet another type of pony. The landscape is littered with pony varieties as it is.
Party pony magic is separate and different from the normal pony magic of the three tribes, or the magic governing cutie marks. It's most likely related to chaos magic.
While it happens less often than you might think, some ponies do change their names upon receiving their cutie marks. (One of my non-parody stories includes this concept; prior to getting her mark, Diamond Tiara was simply known as "Diamond".) This practice is enabled by both Equestrian tradition and law.
Most of your headcanon is lousy. 
Yay, Elric!
Yay, headcanon!
An artificial star would make sense on how it could be controlled by the Princesses. It was probably designed to be, as was the moon.
--Sweetie Belle
5141529
That's my take on things, certainly. I think the power needed isn't so much the telekinesis to move something so massive, but being able to properly connect to the magical control interface.
5141532
That'd make sense.
I bet Infosec Princess Luna (@ShiftOnSecurity) would know.
It was kinda interesting discovering that the princesses have twitter accounts.
--Sweetie Belle
Kirin song!
--Sweetie Belle
5141535
I feel like almost nopony (or other being) could surprise me by owning a Twitter account at this point. Those who don't -- me, for instance -- seem to be the exception rather than the rule.
5141539
I think i actually got one because I was looking at tweets and wanted to respond to one. It might've been Luna's, actually.
It was also interesting to find out Luna's appears to be a system admin and does tech support...
--Sweetie Belle
5141538
I've been enjoying the song demos that are floating around out there now. This one, though, also makes me think that there are probably some Kirin/Karen memes waiting to happen (if people haven't driven that into the ground already).
5141546
There may be some kirin memes around.
So I've heard...
--Sweetie Belle
Sweet Celestia, it's alive! So good to see your gaunt amelanistic face here again! (Yeah, I know, I follow you on the book of faces, blah blah stalker blah.)
I've always seen Twilight and Starlight the same way, Twilight has the more raw power, but Starlight has spent more time refining her power. Twilight is the academic mage, Starlight the practical mage. Research scientist vs. engineer.
Also not a fan of Sombra's portrayal in the comics (which I don't consider canonical, maybe deuterocanonical in some cases), I see him more as an ordinary unicorn corrupted by dark magics.
As for party pony magic and chaos, well, you've heard my theory about Pinkie Pie being the Eternal Champion.
Anyway, good to see you back here. I like the headcanon origin of Equestria, and as for the distant ancestor of the three most powerful unicorns, there's a certain G1 pony who bears a very strong resemblance to Twilight Sparkle's mother, not to mention the shared name, long family history perhaps?
5141557
Or perhaps just parallel realities.
5141558
More Twilights to add to "The Sparkle Census".
I'm so glad you're back after so long, Elric!
Great to see yiu back.I do like your notion on the sun and moon.
I have always considered the Crystal Empire to be a City of the Ancients as in Stargate Atlantis. That's how it vanished for a thousand years. It took off an flew away
Elric! o.o
What about the headcanon that agrees with yours? I suppose that's why the "most" is there.
Good to hear from you, especially such interesting ideas.
Yay!
I haven’t thought as much about some of these things, but I do think that Equestria is the main world, while the Equestria Girls is a subset, not “Earth.”
Of course I agree with you about the party ponies.
There are whole pieces of the show that I quietly splice in with the comics. They’re more closely related than a lot of people think or wanted to think, and I think they got closer, which makes sense now that they’re spinning off to the comic books.
I prefer Comics Luna and Celestia.
I still ship Celestia/Good King Sombra.
I need to catch up with those.
Hey again, Elric.
I find most of this headcanon agreeable, although your stance on comic canon may be a little outdated if you're still following the show. I wanted the comics to be canonical as well, but the show has adamantly persisted in contradicting them at every opportunity it gets.