Palpatine ruled something like 23 years as emperor of the Galactic Empire. He has claimed he wants to "harness the full powers of the Dark Side". But did he actually learn anything useful that he didn't know as a Chancellor?
I'm mostly interested in Canon, I know that in Legends he could be reborn and create Force storms. But in Canon, his powers are mostly stagnant except the little adventure with the Lothal Temple and time travel. Am I missing something?
From the Star Wars Wikia:
After the creation of his Sith Empire, Palpatine established himself in the old Jedi Temple on Coruscant, transforming it into the Imperial Palace. The Jedi had built the palace atop an ancient Sith shrine, in order to neutralize and cap the dark power that sprang from its depths.
During his rule, Sidious sent explorers to unmapped regions of the galaxy to search for the source of the dark side, believing it lay there.
A reasonable hypothesis could be that Sidious was more interested in finding and harvesting the raw power source of the Dark Side than in developing additional skills - or perhaps that the increase in power would infer the gaining of new skills.
