No, Nai: Veitch designed everything up until Dark Lords of the Sith, meaning yes, he did give a rough outline of Sadow and the star destruction...however, in the brief image we see of sadow, he's human. However, Ludo? Gav, Jori, Marka? Those are Anderson's, as is Naga's character entirely. And like you said: Anderson shows a lack of logic often. Hell, Kun surpasses Vodo in a matter of years. Chalk it up to Anderson being a bad writer. While surpassing them may be unlikely, Kun's potential might have been brought out by embracing the dark side to an extent that the light was barred from him, whatever that means.
EE was written during the run of Tales of the Jedi, and Anderson's doing the writing for Golden age...Veitch's images of the ancients are often quite different than what Anderson portrays. Veitch may have created the concept, but the Golden Age, what we saw there, all the backstory and backgrounds was Anderson almost completely.
Like I said: Anderson seems to consider either Palpatine or Kun the top dogs, that's all I know. We've established he's not logical on these issues, you really want me to piece my way through it? And may I remind you it took Luke, Leia and practically the entire power of the lightside of the force to bind Sidious from the Force and he STILL came back until every Jedi ever bound his spirit into the dark side? And Kun gains more and more power as JA grows on and in I, Jedi, from Gantoris's death, from Kyp, from the darkside on Yavin he created...
I really doubt Sidious would've missed learning about one of the Triumvirate in his extremely thorough researches, especially as the Exile and his companions, in the new order likely would've mentioned her. And if NJO and Dark Nest taught us anything, there's no such thing as a gray Jedi. Kreia, by her own admission relies on the force and to quote Atton: "You don't get more Sith than that." if Kreia's not using the dark side here, will she be able to even pull off an instakill against someone as strong as Sidious who's gotten direct training from people she claims make her look like a child with a toy?
I don't think Dooku was giving his all into the force lightning, or a master with it to the extent of Sith like Palpatine. Ian McDiarmid was a bit ticked Lucas gave the Emperor's 'signature move' to Dookui in such a poor way.
Find a new technique in the force, develop something...same as Mace found a way to channel inner darkness, find a way to block a draining attack in the force. And if it can't be blocked, circumvent it. There's no technique of the dark side that's 100 percent infallible.
He beat the other Bpfasshi and then took out the master near the cave. the dark side presence was also contained to that spot when Yoda finished