I think the mission "engine" doesn't really give the devs much choice. Look at the architect.. have players been given loads of choice in the architect? Are we so smart that we've overcome the lack of choice inherent in the engine?
Perhaps the best thing they could do (could they?) is give us a choice of contact, and taking one contact, locks off one (or more) others. That would provide us with choice, I guess.
Remember that in doing so you get this "redundant content" issue which would be expensive in dev terms if this game wasn't so much about rolling a zillion alts.