I love watching my heroes fight. I don't know about you guys, but thats the most enjoyable part of the game for me, I spend money to make my heroes fight in cooler ways and that's the pull for the game for me. So my suggestion is to add a mirror mode for either/or Arena and Crusade. You would not get rewards, or at least very LOW rewards, but you would be able to try out new Arena / Crusade strategies without the penalty of stamina loss, Crusade botching, or Arena chances. This would really add a lot to the game in my opinion and would make me very happy to play it more often.