From a long term perspective, what did he gain from all of the oppression and over centralization of power other than fostering rebellion and instability? Once he was chancellor he could have dialed back the overt machinations continued to exist in the shadows to weaken the Jedi and grow his own power.
Hell, he could have become a sympathetic father figure to the Republic after Order 66 had he just remained as Supreme Chancellor, or even put himself in a position where he could step back and install a puppet successor and maintain the illusion of democracy while controlling the levers of government. Why create an unstable power base for himself when it seemed like he was mainly interested in doing SIth magic stuff in seclusion? Was he just bored?
I would like to see a “dear leader” type of Sith someday even though it goes against that philosophy. I’m a sucker for sci-fi dystopias so I’d like to see more stories like Andor; only a step further, where it feels like most of the galaxy is in support of the Empire(or whatever faction is in power) and you have a “evil corpo” kind of Sith in control. Thrawn is probably the closest you can get but I’d like a character who can tap into the Sith/force lore as well.