I don't think, there were too many monster types, it was exactly right.
I liked act 2 the most in that regard, it was more dark and gritty and the enemies did fit into that very well.
Black Elk: as an arachnophobe, I think we had enough spiders, thank you very much

. Though it was nice to not have all spiders be evil and attacking you. Being the reason of a spider rebellion was nice. But the matriarch and Kar'niss triggered my arachnophobia quite a bit.