Using a one- or two-appearance character to motivate action on the part of a main character! I am shocked and appalled!
There are many methods of motivating a character into action that doesn't have to resort to killing a character. I thought K'Ehleyr was one of the rare highlights of Season 2 and thought she brought a lot of needed charm to what I'd consider a joyless season of TNG. Without her, we're now stuck with the same old "A Klingons Honor is more important to him than his life!" crap that she was openly dismissive of.