The only negative for me, from a roleplaying perspective, is that you're forced to murder at least one person to be able to unlock one of the words. I wish they had made it so you didn't have to kill a specific person in Riften if your intention is to eliminate the DB. Aside from that one of the cool things with this shout is that it's relatively easy to get all three words so you can have the full powered shout at quite a low level.

Murder is murder. There should ha e been an option to involve the authorities. She was abusive, not a murderer. Deserving of severe punishment but death? Nah.

Id see it as more like game limitations but I smell the chicken youre cookin...lol

Awaiting trial like decent civilized folk... but dont you dare kill a goat in that same town. Theyre worth more than little girls.

I used to hate that killing Grelod was a prerequisite but it makes sense. The quest is called Innocence Lost. No matter how hard you try to justify it, deep down you know you lost a part of yourself when you killed her. I even like that you have to do it to destroy the DB because you get a ton of loot, the Blade of Woe, 3000 bucks, and a word of MfD. But only for those willing to have blood on their hands. You can't righteously kill a group of assassins that are objective towards their jobs. It makes you no better.

"I don't care if you're the only one that can save the world, Dragonborn, you killed that chicken so you must die!" - random guard #214

They only try to kill you if you fight back :D

I actually once got into a fist fight with a goat in real life.  The interesting part is that I lost!

I've fallen in love with Marked For Death with my recent monk build.

For PC users, there's a very elegant solution to the problem Marked for Death has someone made into a mod. It adds an additional effect on Marked for Death so when it wears off initially a buff is applied to regenerates the armor back.

http://www.nexusmods.com/skyrim/mods/55651/?