I've never really been a fan of "scouring for plotholes" - every film in the history of ever has plotholes, because films are a creative endeavor and sometimes things happen because otherwise the movie would be 2 minutes. Doubly so with fantasy/sci-fi/space opera.
I rather enjoyed the sheer absurdity - a good thing! - of Palpatine's power and resources. It showed that as the last inheritor of the Sith, he basically was the ultimate BBEG. It doesn't really matter, in my opinion, how he amassed it all - or even survived - because if this dude is wielding the apex of the Dark Side and the Sith power, then yeah, it all works.
But, because I'm in the Deep Lore with Star Wars, it's entirely possible he's been working on this since the OT, using everything gathered from Thrawn's intelligence, to Imperial scientist work, to ancient lore of the Sith, to whatever else. Dude clearly plans everything beyond anyone, and was trying to play 4D chess with everyone, but couldn't see the threat right in front of him because of his hubris.
He relied so much on the Skywalker bloodline, and the susceptibility of them to the lure of the Dark Side, that he didn't see that by casting aside his own flesh and blood, they would ultimately be what undoes him. And then said flesh and blood embracing the name of the family that played the biggest part in his final demise, including turning his own against him? Ultimate **** you.
Edited by StarkJunior