Another option, as many have said, is to plant the seed at the end of TLJ. One thought I had is that so much is made of the Resistance sending out a signal for help, and no one answering. It’s reinforced again in TROS. What if they did get an answer, from Palpatine? The radio crackles, and maybe we just hear his iconic laugh. Just a tease at the end to build up anticipation for TROS.
I know I’m late to this convo but that sounds incredible.
The one thing I wished we saw more of was a connection between TLJ and TROS. Bridging those two films together would have helped things immensely.
I wish there was some way to go as far as Rey’s parental reveal happening in TLJ, but I don’t know how it would work.
Why not have a mention in the opening crawl that Luke’s actions on Crait has ignited a spark of hope throughout the galaxy? Or have a mention that many of the ships were inspired by Luke’s actions to help Lando and the Resistance in the final battle against Darth Sidious’ forces?