What difficulty were you on? The missions weren't epics that had unqiue mechanics, but they had unique settings and certainly took me and friends longer than that on Extreme - the mine missions especially (albeit thebackdoor entry would make it a very quick run if you knew about it beforehand!
The bolded is exactly what I'm talking about. Artificially ramping up the difficulty does not make the mission any less boring. The way the torture couple was played up in their intro video I was expecting their location to house some super morbid stuff. Perhaps they'd have a corny speech or two, and a bloody monument somewhere. Actually the last room with the chopped up cadavers was when it started looking interesting, but that location really should've been on the 2nd to last mission. With the finale being a chase or something. It would give your targets some character. But as it stands the bosses could have been put in a shed and it wouldn't have made much difference, it's just another tick in a checkbox.
It's just not memorable at all.