TC_Liyanage1
Personally I think the first movie is near Perfect. the only thing to fix would be the Obi-Wan vs Darth Vader fight. It could use better choreography and Force pushes mixed into the fight. Maybe add the Biggs Darklighter scenes to the movie, regardless of the pacing. For other movies I would argue setting up "Heir to the Empire" as the 4th movie to the OG movies(A tetralogy). Where Han and Leia have babies, Luke meets Mara Jade, and Admiral Thrawn is the enemy. This way after the original movies you can do the "Prequels" and then come back and make a true sequel with the kids of Han, Leia, Luke, and Mara Jade facing the remnants of the Empire controlled by Admiral Thrawn.
Use real world events and historical inspiration to build up the sequel trilogy and use Legends as a base to build up more lore and worldbuilding. Keep the original and prequel trilogy mostly the same albeit with minor and moderate changes like no jar jar binks, cringy lines, and Padme being 5 years older than Anakin. Also hire linguists and conlangers to help create different in universe languages.