<p>4.4 looks like it. Obviously have to have 5-starred the mission to get the xp. It has an epic boss, a boss, and 2/5 of the missions are high difficulty thus more xp. I know you don't need CP, and that isn't the basis of my recommendation. 2/7 are bosses, 2/7 are high, and 3/7 are medium. Best turnaround.
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