Things now canon in the Crookedheart AU (just to keep track of stuff), starting with the obvious:
--Rainflower's name is changed to Crookedheart.
--Stormkit stays Stormkit and eventually becomes Stormshell and then Stormstar.
--Oakheart's name probably changes too to stay different from Crookedheart (maybe Oakmist or Oakcall).
--Hailstar and Rainflower are littermates, and when they were young Hailkit admired his sister and looked up to her.
--Crookedheart loses custody of her kits because Hailstar feared she would take her anger out on them (especially Stormkit). They are raised by Shellheart and Echomist, along with Volekit, Beetlekit, and Petalkit.
--Hailstar is a good uncle.
--Shellheart eventually moves on and becomes a mate with Lilystem (because she was the only available option, but I also like the callback to the mistake in Bluestar's Prophecy when she was called Crookedstar's mom).
--Shellheart has 3 or 4 kits with Lilystem (possibly different litters).
(these are their designs btw. Their names aren't set in stone, so feel welcome to suggest some)!
--Mapleshade is still involved, just don't know how exactly.
--As leader, he creates a new code: parents who mistreat their kits lose custody of those kits.
--The code extends to Shadowclan, and Brokenkit is taken away from Lizardstripe (her bio kits stay, she never does anything against them). He is given to Brightflower (my new Brokenflower AU). Yes, he still kills Mintkit and Marigoldkit.
Always welcome to add more!