I think both treatments, Trevorrow's and all those of Abrahms, showed that another film was needed to give each character their due and get them to where they needed to be in their endgame. Even if there was no Last Jedi, this always felt as a long game to justify the repetitive backdrop and set-up.
I know some fans would cry that Star Wars has to be released in trilogies just as much as them being "events" make them magically better, but the angle has always focused more on this being a part or conclusion to a saga more than anything else. So cash in and do the Harry Potter, or perhaps more relevant the Avengers, method of splitting your concluding story into two pieces to cover the necessary ground.
Finn's trooper background that was played with in TFA and almost made it into TLJ could pay off. Palpatine could be revealed in film. Kylo's shift can be eased, maybe with a ghost convo with Anakin (no longer being blocked by the influence of Smoke/Palpatine) who uses that Han moment to not only give Ben that peace of mind knowing what he's doing is now right, but to hammer home that the things they've done are irredeemable and all they can do is make sure their final acts, before the Universe's judgement claims them, are done out of love free of anger and hate. Build Poe as a leader who grew from his mistakes. Have Rey build her own identity into what she wants it to be instead of passing it between various players on a switch.
In many ways I'm upset about this film in the same way as Revenge of the Sith, though the latter somehow managed to let it's events breath enough to somehow work despite being a bit tame and underwhelming.
