Interesting take on those fights.

Raphael: This was a tough fight for my party. No illithid powers and had an unbalanced party. Gale's Counter spell thwarted Raphael time and again. Minions were tough, I actually needed Hope's help a lot.

Cazador: Breezed this one. Dimension doored to Astarion, second companion freeing him. Had a host of summons to block Cazador drawing power and ranged him to death.

Orin: A complete joke, except... 2 companions yeeted to death after Orin's death. The 'minions' posed serious threat - again! Reexamined everyone's athletics, acrobatics and resistance to forced movement afterwards. Gale started chugging Str potions from then on.

House of Grief: 4 hour fight, apparently. I took the experimental B-team there. Fight broke out, summoned a Deva... got rekt. Plan B time, Astarion needed to escape and rez the party, but shadow stepping Sharrans kept getting behind us. Anyway, noticed Jaheira's (Ftr/Dru) Sleet storm was breaking the horde into manageable squads that were funneling up to break on my tanks. Daughter came home and said 'Dad, that's been like 4 hours!'

To me, it seems like party composition, spell selection, items equipped and character paired combo's matter a lot. Have to say, I don't consider any of these Act 3 boss fights easy on tactician. Personally, I need to watch those minions, they often hit hard.