But then that's always what I say about JJ Abrams movies trailers before being disappointed at the end. Still, there's potential here!
So, if Palpatine is back in some form, does that mean that he was behind the events of this new trilogy too? Perhaps Palpatine's ghost guided the rise of Snoke, and guided Kylo Ren to kill him, thus completing the transformation that he didn't manage to do with Luke. And somehow Rey will prevent this. I'm sure Abrams will retcon Johnson's film a bit and make Rey's parents somebody important, perhaps she's a Kenobi. We'll see.
I'm not the biggest fan of the sequel trilogy up till now, there are some good things and there are some less good things. But I really liked this analysis which focuses on the good things: how this trilogy's characters comment on the previous trilogy's, thoughts about building a future vs holding on to the past, the weight of responsibility, self-reliance, how heroism was perceived in the 1970s vs today...
When The Last Jedi focused on Rey and Kylo it was excellent. I hope the last one delivers on those themes.