I've kind have noticed it too. All the bosses. I nearly died to Moder like thrice now after the AI updates and I've noticed they've become quite aggressive with their specials. Yagluth spamming meteor and Moder spamming her flying ice splinter blasts. Even with the classic dark souls role, she curved her attacks and i ended up tanking 4 splinter blasts nearly dying. Yagluth just nonestops spams the fire slam and meteor, but once you get far to recover, he's still slow. Overall the best AI improvement went to Moder, also noticed that she does not get stuck at areas as she used to before.