We’ve been playing quite a bit of KoW3 - there are bits of rules that are harder to find than they should be. But overall there aren’t that many pages of rules so its not too bad.
As with most games its the various special rules that are the complex / hard to remember bit. But at least with KoW its one list of special rules that are applied to all armies, rather than each army having their own special rules.
Sounds like a typically brutal KoW game, with lots of units getting killed mid-game.