Still on the side of bringing back the dead trolls for Act 6 to help and be with the Alpha Kids and their session. Maybe have some of them confront with the Cherubs as both Calliope/Caliborn are antagonists. Both represent the fandom of both good and bad in the worst traits. The trolls and kids would have to find a way to stop them.
In another scenario, have some of the dead trolls be with John and Jade during the ride for the Alpha session. Part of it could be an excuse to separate Eridan from Kanaya so she doesn't kill him again and he gets put under watch if he tries to pull anything. The trolls would confront the kids, conflicts about human vs troll standards in things like morals and quadrant relationships. Soon, they come to an understanding and agree to help each other out as friends. Davesprite as well would also have a chance to talk with his counterpart self to help give closure for his identity and knowing that a version of him will live his best life with his friends and the people he loves.
Maybe have the once dead trolls keep an eye on the Alpha session and talk with them via Trollian while on the meteor. Let even the Beta Kids use it to talk with their descendants. Friendships blooming, possible ship hints for some, all working together to stop Lord English, The Condesce, Jack Noir, and Caliborn/Calliope. Each group fighting against them. One group of trolls fights Jack, Karkat and the others go up against The Condesce, Beta Kids get Lord English, and Alphas with Cherubs. Have assists from Nannasprite, Jaspersprite, and Davesprite.
Once bad guys defeated, they all arrived on Earth C, Matriorb was made after Roxy have trust in the trolls, Wayward Vagabond is still present, no kingdoms, every country lives in democracy, and people can choose endings however they please. For me: JohnVris, DaveJade, Rosemary, Karezi, EriRoxy, FefNep, Arasol, DirkJake, EquiusJane, WVPM, Tavros making a special organization to make sure the animals on Earth C live peacefully with the citizens that it will be an allegory of how all of them are now living in Eden Paradise.