Cornerverse

So, I have a lot of things in my drafts and as time goes on and they remain unfinished, new episodes and comic books come out and either confirm or disprove my headcanons and stories. Some things I could adjust as time goes on, like how the OC I had made for Diamond Tiara's mother is now her aunt(and future step mother) since we've seen Spoiled Rich. But certain stories, like one for Sombra's backstory or the one for my headcanon of Fluttershy's parents, would have to be scrapped completely. And don't even get me started on my Next Gen stuff.
Anyway, what I've decided to do, is put all of these into an AU. I call it Cornerverse-MLP, though will be just 'Cornerverse' for short. Season Four and the first three Equestria Girls movies are all canon to Cornerverse. Comics and Story Books are not canon. Any events that happen or information is revealed from Season 5 onward, is what I call 'pick and choose' canon. Basically, I can keep what I like and take out what I don't. Some examples off the top of my head:

Starlight's story and Sunburst being a dork? Canon to Cornerverse. The new Alicorn Mythology, and the new Crystal Heart lore? Not Canon.
Spoiled Rich and Diamond's redemption? Canon. The CMC's Cutie Marks and Diamond's revealed talent? Not Canon(they get their marks that day but not those specific marks).
Fluttershy's parents and brother? Mostly not canon.
Dragon culture? Not Canon. Changeling reformations? Canon(but I might tweak their actual design to look a little more Chrysalis-like(giving them actual eyes and also manes).
Hearthbreakers? Not Canon. A Hearth's Warming Tail? Canon. Hearth's Warming itself is in a weird gray area with conspiracy theories.
Legends of Everfree is 96% canon except for 1. Sci-Twi being an Alicorn now 2. Some of the Midnight Sparkle stuff 3. Filthy Rich isn't as much of a jerk
And so on and so forth. I'll put in the description which stories are related to the Cornerverse, and possibly tag it with 'AU' if it goes too off the rails, maybe even link to this blog post to clarify the AU for new readers.
That said, if you want to ask specifically what is and isn't canon to Cornerverse, you can ask here in the comments and I'll give an answer.