I would go with the get impaled by SEVEN. That way it could be like a movie death. All dramatic and stuff. It would cause death quickly but still be dramatic. The others sound way to slow other then Shiki. I think his move would look cool in slow motion.
I'm a pussy and I'd rather not feel pain so... Shiki is the way to go
"I settled for that shriek. Those dull vacant eyes... oiled cabbage stench of her...! [...] You know what? I'm sorry if I'm not gonna do this the way you want me to or the way you might. But I will not make an angel out of someone who wasn't an angel...!" -Chief Tyrol, on his beloved wife. Have you heard about the saying that goes something like "drunk people and kids tell no lies"? Well, that's just a fallacy.
Fuck all of those. None of the above. My death of choice:
Death by snoo snoo.
"We have been the cowards lobbing cruise missiles from 2,000 miles away. That's cowardly. Staying in the airplane when it hits the building, say what you want about it, it's not cowardly." - Bill Maher