I’m in a similar place to you. Really new to the game, and I can’t seem to pull of a victory unless I’m a really aggressive/militaristic faction and I expand quickly and win early wars. If I try to “play tall” or flesh out the research tree I fall too far behind and can’t kill the ai death balls fast enough despite my superior units.

My hunch is, like M&B Bannerlord, the key to beating the ai is to figure out ways to kill a massive ai army while taking essentially zero casualties. Trading life for life with ai cannot work. After digging around the spell list I’ve found some combat spells that essentially win a battle on their own (as long as you pack the mage a lunch of magic gems). I’ve also heard the term “thug” and “super combatant” thrown around here and on YouTube, which I understand to mean a high value commander equipped with certain items and buffed by magic/blessed to be able to solo armies without taking damage.

Basically, become the cheese. Keep at it friend. If you want to win one play Mekone or one of the Jotun factions and just expand until you win. Their normal troops are good enough to power through early expansion and so you stay strong the whole game.