Personally the last line doesn't bother me as long as the book ties up everything in the story.  But that only applies if it's a stand alone novel.  If it's like The Dresden Files for example then I know what is covered in one book mightn't apply until further down the road.  So for your answer no it doesn't bother me if the last line is amazing or not.

I agree with your teacher. Because after the first line / paragraph I can always tell if I'm going to like the book or not.

Your first lines:-

"What the h#!! is it with Vampires and S&M clubs?!"
"At what point does the human mind break?"

I really like these first lines.

Any chances of Jim Butcher coming to the UK anytime soon?