I am working on a fixfic, if anyone wants to help or just make suggestions we can talk in private messages and share in google docs.
After the events of Ending Of The End the trio was safely transported back to Tartarus where they unfroze them and Discord was banished to his chaos dimension. Turns out Discord was actually manipulated and threaten by the real Grogar to abuse the trio and attack Equestria but he has to keep it as a secret. Over the years they allowed him to visit Fluttershy in a limited time but he must still spend most of his time in his dimension.
Around a year after the events of Last Problem Flurry Heart and her parents visit Ponyville for the Summer Sun Celebration and take bedrooms in the Friendship Castle where Trixie Lulamoon, Starlight Glimmer and Sunburst live with their daughter, Luster Dawn who is the protagonist. It is revealed her and Flurry Heart's parents used to make their daughters get along as foals, Flurry Heart wanted to befriend her but Luster Dawn was uninterested and was only interested in studying, since then Flurry Heart holds a grudge towards her. Luster Dawn wants to prove to her she changed resulting some bickerings. Meanwhile Twilight Sparkle asks Luster Dawn if she wants to help the trio in reformation.

There is more to this but i do not want this to be too long and show too many spoilers, i can talk more in private. I think chapter one is done and i am currently stuck in chapter two.

sounds pretty good to be honest

7534674
Not a bad idea overall. Sadly, I suck at giving story tips, but I do like this, even if the trio in Tartarus saddens me.

7536101
Same. The trio were the best part of S9 if I’m being honest.

7534674
Wonder how things are going for the Royal Sisters there?