So, mathematically, the number of slow time events positively effects a game. Case in point; Stranglehold, Wanted, Army of Two.
Instead of introducing quicktime events during cutscenes, introduce slow time events during gameplay.
I was playing Wanted today. There are a few times when your character goes into rail-shooter-slow-motion-awesome-time. These could have been done a just cutscenes or they could have been made quicktime events (pull the trigger but don't aim) - either of these options would not have been as cool as seeing time slow down and my guy jump and dive between enemies in slow motion. I didn't have control of where to dive, but I had control of aim while the game dove me around - and to make it even better, the dives between guys were regular speed, while the time I had control of the aim was in slow motion.
Take note future game devs, quicktime sucks. If your game has it, you'll probably lose sales.