Managed to keep Chaos at bay. Two very hard fights against armies that the game said were stronger than mine.
In one case I managed to assassinate one of their heroes. That certainly helped.
That and the great tips I got here. The Grave Guard with two handed weapons are great combined with some summoned Zombie chaff units and Black Knights flanking. I even made a circle charge once or twice.
The game called both Pyrrhic victories but I recovered well because of my good heroes and commanders healing.
The third and fourth big Chaos armies were defeated by Karl Franz and the Dwarves. And fun fact: everyone likes me all of a sudden!
My fight against Chaos and the Greenskins (thoses Greenasses started a Waagh in the west while I was fighting Chaos in the east so I killed everyone) helped my reputation so much that I now have a lot of treaties with almost all of my neighbors.
So a little bit of breathing room is there and now I am moving into the former empire provinces that Chaos left empty.
...so they actually helped me, in a way. I didnt have to fight the Empire and their allies. I merely moved into the ruins of their cities.
Btw what is Mannfreds best mount? The flying horse looks kinda meh. Fast but a lot less armor and less attack... The Dragon looks cool but it also is slower... The best hitting and armored for melee fights is the first horse it seems? What am I missing?