Alright, tested out the Waves difficulty with the new bosses and new AI. The experience is much improved and the bosses are great! I feel like I don't have to do all the work now. But the problems with the stone walls are enhanced here. The archers have a dead zone close to the tower, which is realistic and fine, so to avoid that the best shape for a fort seems to be a four pointed star. This is a more complicated shape with, you guessed it, more corners.
Oh, also I started decoding the tablets and I must say, these aurochs were quite full of themselves xD