nearly every coop idea i think of is having one big issue: ingame time.
f.e.: what happens to the other player if you are participating a tournament or a siege? is the game going to be paused, is the game time going to slow down, is the time just passing by? the current multiplayer mod is at normal speed all the time, which is slowing the game down in a crazy ammount. advancing forward becomes painful and only very ambitious players stick to it for a longer ammount of time.
no matter what, the game is having limitations which is going to make the experience less pleasing as playing alone.
there would be another take: one is controlling the party and the other is part of the party, just as a companion. so he is only participating in battles/sieges/tournaments. this is kind of odd and not as interesting as the real idea, to have both players as party leaders on the map.
as much as i like the idea of a coop mount&blade experience, i do think its a theoretical nice thing, which is just very difficult to translate if you think twice.
. I really appreciate the changes!