I forgot how much failed potential is in this game.
The battles are the only really decent part, campaign AI is completely broken. There's a plateau for starting in the middle of the kingdom because capturing everything in Vlandia/Battania/Empire = constant AI rerouting between Garontor castle/Quyaz and whatever is being attacked on the other front usually Lycaron/Chanopsis castle, whenever Garontor goes down quite literally everyone drops whatever they're doing and charges full speed across the continent, ending the Northern Empire that only has 1 town left? Forget it, let them take their shit back. There's a weaker force that is currently attacking Phycaon and we're marching right next to them? Nah dawg we gotta move to the other side of the continent rn. Having 10m+ means nothing because of the ridiculous decision making patterns and cheesing required.
AI armies will sometimes also run around in circles endlessly chasing small parties that are trying to go somewhere near them. There's no way to spend influence to tell them attack something, and you're not requested to do so by a marshal. You're completely at the mercy of random AI decision making, once the game is close to finishing I guess devs decided to be jerks because every enemy army mercs included suddenly had maxed out parties of 200-330 units.
Campaign tactics boils down to waiting for an 800-1500~ army to attack something, waiting for the assault to start, then breaking into the town so your 300-500 stack will auto resolve because it's always the most efficient (you can also win by making them retreat if there's enough siege equipment to break their siege weapons but there's no reason to do this they lose less troops than auto resolve). Even on hardest difficulty AI will never siege intelligently like by breaking both walls they universally always attack towns with unfavorable odds.
Sieging also takes way too long the speed up button isn't enough. Cheesing AI siege and imprisoning all their nobles over and over is probably the easiest way to win but it's very repetitive. I haven't tried executing them, it tanks relation with almost everyone but I don't know if -70/-100 relation does anything, haven't tested but knowing the game they'll probably start defecting.
Getting nobles is a grind but it's easy with smithing, but the issue is everyone will hate you for not giving them fiefs, and even if you give them fiefs they still tend to betray you at RANDOM or with no warning and join other nations despite relation being 100 destroying all your progress. Also can't hire mercenaries, only if you're a vassal will your host country randomly hire them. There's zero interaction with politics in any way other than higher relation making it easier to convert enemy nobles.
I've done two campaigns now routing down the middle because I figured it would be faster to respond a separate front so next one is going either through Sturgia or Aserei early. Haven't tried murdering nobles at all because I focused on releasing + poaching but probably will try that next time.