Kael’thas did become more paranoid enslaving his blood elven pilgrims, wiping out the Kirin Tor on Outlands with a mana bomb then attempted to blow up Alleria Stronghold that held second war veteran high elves, pushed the Draenei out of the Naruu ships to devour the Naruu, and even attempted to use Lady Liadrin to siege Shattrath.
I suspect he’ll stay away from many people, least he hasn’t burned his relationship with Jania.
Look. We all make mistakes. That’s where the bronze dragonflight comes in. I go back in time, off the dragon, and go back to the present to be with my one true love that’s never been with a dragon.