Sul? I don't think so. He seems like a die-er, so I predict he dies in the next book. I just want Colovia to secede. The Nibenese are awful.
To be honest I have no strong preference about what race or sub nationality ends up ruling Tamriel. I'm just rooting for the good guys, which in this case are the people who aren't psychotic wizards using a greater Daedric soul fragment to raise an undead army.
I've noticed a trend of people saying they regret that the Empire always wins or that they have to help the Empire in games, or have to root for Imperials in the novels and other lore.
While the Empire isn't a perfect system and the people who comprise it aren't perfect races, consider the alternatives. You could have had a world ruled by Ayleids who delight in burning children alive and making furniture out of human skin. You could have had Dagoth Ur spreading the blight across the entire world, or Mehrunes Dagon stomping around, or the Aldmeri Dominion practicing eugenics on a massive scale, or savage Akaviri invaders doing gods knows what. The Empire may be the lesser of two evils in all these instances but the greater of two evils is usually more noticeably - well - evil.