I've read some of the comics, but not that far, although I have been spoiled as to who the victim is there. And without reading it, I understand why comic fans would be angry, but if AMC refuses to kill major characters at this point, does it even matter? Isn't the significance there who gets killed as much as how? I feel relatively confident in concluding that AMC's Negan just took out a B-rank character at best.
Oh, and I don't disagree about the random hiccups of the season finale. As usual, the show is just plain stupid sometimes. Like Rick & crew seeing the chained up walkers, but not checking the embankments on either side of the road before moving to take down the walkers? At times the show portrays Rick & crew and shrewd and calculating, then other times they're just buffoons. But overall, this was a good season finale. Tension was high and they were doing something a little different than they've done before. Overall, popcorn entertainment like usual, but more solid than some of their recent endeavors.