I had an overly complex and hilariously ambitious idea on how to fix Anakin before and during the final battle with Obi-Wan. But let me point out my thoughts 😛

Restructure the end of ROTS, so that after Obi-Wan went to ask Padmé for help in is quest to duel Anakin, 3PO contacts him during the night, because Padmé was poisoned. Obi and 3PO fly her to Mustafar, where the early Rebel alliance has been formed (note, the separatist were sent elsewhere). After their arrival the medical droid attest that she has been poisoned and that they have to operate quickly to save the babies (cut Yoda and R2s presence).
After the birth of the twins, Anakin shows up and confronts Obi-Wan, during their fight we see the Tantive IV leave, Obi-Wan follows soon after.

This way Anakin would have an actual reason to fight Obi-Wan, who denies him to see his dying wife and new born children and it would explain his hate against the jedi and show the manipulative nature of his relationship to Paladine: Although it seems unreasonable for the jedi to kill Padmé, it is the only thing that Anakin can allow himself to believe. Because otherwise Palpatine, the only other person involved with this whole mess, needs to be responsible, but that would mean that there is no way of getting her back, which Vader does not dare to believe.

P.S.: Although many of these switches seems impossible to pull off, I have managed to both change Polis Mesa to Mustafar and create an alternate beginning for the duel.
The only thing still missing is 3PO informing Obi-Wan, haven’t got an idea yet, maybe I could use some footage from the assassination attempt from AOTC, idk… Anyways I would be very grateful for any help or response in general, stay safe to you all, I appreciate anybody who took the time to read 😄