Play it on hard and not ONE second you feel like your waiting for a next event to trigger because you're too busy not to die.
There's also plenty of paths to take, sure the goal is the same, but if you need to storm a villa, you can do what is expected (enter through the front door) hold a firefight there or .. circle around a balcony. and be greeted by enemies. why? because it's ultimately still an open world that has been filled with scripted enemies because the devs thought about it.
Hard is the difficulty any seasoned FPS player should be playing at. It's not nearly as bad as MW2 on Veteran (MW2 on consoles atleast). I played through the first few levels last night and it was seemed OK. Nothing engaging to the point where I feel like I have to play it insead of the MP. The QTE's have no place in a FPS games, personally.