Anakin Starkiller said:
Am I the only who feels like it isn’t really Star Wars without Palpatine pulling the strings? The thing is I can’t think of any way of bringing him back that doesn’t cheapen Vader’s redemption. The best I can think of is Palpatine survives the fall (he IS a Sith Lord, so I think it’s totally plausible), but is seriously injured, meaning Vader’s sacrifice still had an impact, causing Palpatine to remain in the Shadows for 30 years. Still, you can see how it devalues that moment in RotJ. The thing is, with Palpatine gone, everything else feels super post-script. Now that’s fine if you really want to tell a brand new unconnected story, but clearly they don’t. Besides, with both Palpatine and Snoke out of the picture, the trilogy just lacks any threatening villain at all.
If you absolutely must have Palpatine in some form, simply have his spirit (or the combined spirits of all murdered Sith) wander the galaxy after ROTJ before inhabiting Snoke sometime before TFA. Then when Kylo murders Snoke, he ‘inherits’ this Sith essence.