Uh, what did you mean by spawn? There isn't creep spawn, they are there since the beginning of the gameplay(a realistic think in my opinion thought, monsters aren't infinite)
The campaign is only repetitive after giving up and even then I think it becomes quite boring with lots of gold. The challenge isn?t as hard as I expected during Hard+ with the 3 having the best items available.
I wouldn't say boring, but yeah it makes the gameplay much easier and the Hard+ difficults not that hard. And of course the campaign it's repetitive after giving up, but i wouldn't say that much on the FIRST give up, since there are somethings that you haven't done on your post play.