I completely agree actually! I thought that Fallout was the best MI film by quite a distance when it came out - I've seen it a number of times since, it's fantastic. I was excited for Dead Reckoning, but was disappointed. And the way that Faust is killed is, frankly, completely undercooked. It's terrible - the characters move on so quickly, Faust isn't even given a moment of mourning. Ferguson is a great actress and Faust has been one of MI's best characters, so it was a disappointing farewell as you said.