I'm very against bring back dead characters. But it's understandable since Rian Johnson killed Snoke.
Palpatine was simply embodiment of evil in EP6 to act as the big bad and redeem Vader. In PT he got a lot of development to show us his disguise of a charming chancellor and the grandplan to use the Clone Wars to become the Emperor and eliminate the Jedi. It was highly praised.
I hope he gets some development in EP9 like he created Rey or Kylo to fulfill his goal instead of repeat his EP6 self again.