I find it strange your mc's go from regular people to somehow world conquering maniacs in a matter of seconds. Don't get me wrong its not bad just a real 180 in personality.
Thanks for the chap! Can you try the better governance than other kingdoms route so the peasantry and magical beings prefer Duloc over others, making other rulers livid and attacking you first? Making conquering their territory valid.
Please look up Hazzor video "Can For lead Conquer the World with a Horse Horde in Mount & Blade Bannerlord?" It is really funny and it could inspire writing. Or just give a laugh.