My personal preference for the Death Pit would be to take the basic wheel shape of the circular area around the elevator shaft and just duplicate it to near infinity and make it darker all the way down.

So Palpatine falls down through all the segmental gaps (like the one he was thrown down at the top).

He wouldn't have a chance to jump to the next floor because the air friction would make him explode (besides it's a PT style superhero trick of the type that needs to be toned down in PT re-workings).