That's why I suggested that his throne room be changed to exactly that.

A room which moves from place to place.

Having it rise from the a building on Coruscant and perch onto the tower of the Death Star creates the impression that trappings of power mean nothing to him (all he really needs is a chair and a window), power is all he wants and he is convinced he has it all already.

This is why he shouldn't have had a Jedi weapon in ROTS, his ego tells him it can defend itself without the need of a machine.

He is the mirror image of Yoda.

Outwardly frail, he commands the power of the Force (only the dark side of it).