The thing that bores me to tears with coop play is waiting for the person you're playing with to end their turn, it can easily take 10mins or more, especially if they do a battle. So for the love of Sigmar, improve your COOP experience, I'm so sick of waiting, what feels like forever, to do my turn.
Shogun 2 had a better COOP mechanic where you could manage your settlements and set up queues during your friend's turn. Why was that removed? Please return it.
Wherever it is COOP or Head to Head, I think both players should be able to share each other's turn in all things except military actions. I'd even like diplomacy to be shared across turns.
Also, for the love of Sigmar, allow the COOP player to the ability to attack enemies without the other player being required to confirm by AR or spectate, etc. This mechanic really slows the game down and I wish it was optional because I'd like to be AFK on their turn and if they attack someone when I'm AFK they get held up because the game is waiting for me to choose "Spectate" or confirm the post-battle results. This is not necessary, it wasn't my battle. In Head to Head sure it makes sense if the other player wants to play as the enemy AI, but the players should be able to disable this mechanic if we don't want to use it, or some kind of timer should be placed on it for how long the other play has to decide. I'd choose 5 seconds or less personally.
Please CA, consider this suggestion and implement a better COOP system in future games/updates.
To better understand my frustration and suggestion, today I played a few hours with my friend, I spent half the time just waiting for his turn to finish. So if I played for 7 hours, 4.5 hrs I was spent waiting for my turn. It builds up after a while, and my impatience turns to frustration. I really wish in COOP our turns were shared, aside for things like military actions for obvious reasons.