Ooh, that's a great question!

Also the perfect excuse for the Star Wars fan in me to geek out for a bit.

A disclaimer that I would still want to have access to the original versions of the movies. But I would change the famous twist in The Empire Strikes Back so that Luke and Anakin are not related at all. Even though I
do think it's a great twist, but at the same time it would have been an interesting "what if?" to see how the rest of the Star Wars story would've played out without that revelation, since it completely changed the trajectory of the series from that point on.
Also, even though I love Return of the Jedi, it would also have been interesting to see how future of the franchise would've played out if RotJ
hadn't been rewritten to wrap up the saga right there and then, as per George Lucas's original plans.