I think killing a character in a Naruto Rp would be power abuse. 
You killing my Genin with your S-Rank ninja is pointless. (Especially considering that I, by making a Genin, was actually following the guidelines that were originally for the Rp). If you want a death match then have a fair one with a character of your own rank. Don't just pick a Kage spot so that you can freely kill all other character's in the Rp. That's retarded and, in my opinion, it's retarded to think that makes sense. 

You don't need to kill characters at the end of a fight. Could just beat them to the point in which they can't move or are "almost" dead. I didn't take all the time and effort to make my character just so you could rage kill them. There's plenty of character development I could do with my character upon a defeat and the Rp can contuine on, instead of it just being hollowed out with my dead character. Kills are wasteful. Especially if you do it in a cheap way like an Auto-hit because your character is "faster" or "stronger" than mine. A good Rper doesn't need some high class or higher, technical, rank just to win in a fight. Spam and abuse. 

Now, if it were a fight between my S-rank ninja and your S-Rank ninja (or if we did away with the technical rank and fought as equals) I'd accept any death on my character wholeheartedly. However, otherwise, I refuse to have my character killed for bullshit reasons by a spam player. I will powerplay the shit out of that entire situation.