Chapter 2 was a pain in the arse for me so far, for a bit I had to deal with 2-3ish invasions per turn between green and red, after green took over yellow's capital. I eventually won through by instead of leaving one or two units in a territory as a defense force, I consolidated my forces into more response battalions that were in a central spot that could respond to an invasion of multiple different territories in a single move. It was a lot of tug of war but things started to steamroll nicely once I took over yellow's old capitol. I wasn't all that nice to the undead goober (30% popularity, eep!) and Red's capital island being undead I had a terrible time of capturing it. I had a VERY small army which I used almost exclusively for capturing and very small engagements, and for shelling the capital building once I cleared the way, but that map my dragon basically carried the day. Was bloody annoying too as the AI had warlocks EVERYWHERE.
I had the same issue of Maxos congratulating me for killing a sibling on every turn as well, I was starting to wonder if someone took away his brain medicine.