I agree that the mission lengths lead to fatigue! Some stuff goes on too long, despite being amazing in its own right all the way through. This can be exacerbated by the order of the missions, like going from the labyrinthine Death's Dominion to the equally winding The Brand.

I wouldn't say the mission goals lack variety - yes, pretty much every mission is a robbery, but 2 of them are tomb raiding, there's breaking into an abandoned mansion, recovering an item you lost, a mission that sta...