I have time on weekend, so I finished WK. Some opinions:
Orc horde: was very enjoying and great. I was thinking if they stop to come at all or shall I loot the pool or do sthing else to stop them. Anyway I decided I hold while I can. I still left plenty of resources (spells, usable items) when they stopped, and I did ancient dragon and machine without a rest after the orc horde. This was that kind of encounter what I likes more: some harder enemies which are cared by my fighters, and many medium-weaker one which are handled by my casters. (Another example for this are those assasins in post Firkraag quest.) Anyway, I think some of the orcs should be a bit more difficult, I mean weaker then those mages, but harder than reguler orcs and archers. And I vote at least 1-2 more waves.
Ancient dragon: very good fight. My only comment: I have found last part of the dragonlord here. I don't know if this is intentional or not, and I don't remember if there is any dragon left in the game, but I think there is no reason to be able to craft that item which is best against dragons only after the last or hardest dragon in the game...
Machine: improved stuffs were great. I kept ultragolem and elemental golem to summon max. golems, before I killed them. It was a bit hard at end, since I was run out from spells cause of orc horde and ancient dragon, my chars were exhausted. So at the end I have 2 amber golems, 2 coin, ultra and elemental there, since I was not able to kill enough fast the last summoned ones. Anyway, I did it. Those mages were craps btw, so some improvements would be fine here.
Guardians of the seal were easy, and that Demogorgon was a joke also for my party... Imho you should make this harder, Sikret, since it is intended one of the hardest battle in the game. Now any improved ToB fight is harder than he...
Anyway, less experience from mosters, and nerfed level table will be great imho, I think end game will be more challanging in 4.3. Now Haer and Anomen has max. lvl in my game (lvl 40), and I have just got Yaga's heart...
And I just realized I haven't found Holy Scabbard for Holy Avanger. Where should it be? Anyway, it is not so big loss. Best feature is 50 % MR, Keldron now has 90 % with that sword, but I am nowadays using 2handed Daystar, Purifier etc. with him, and soon I will have JD sword, so he will use that.