Personally for me..I wouldn't mind getting a few Losties out of the way. Whether they are annoying, pointless characters, or for some reason they just bother the hell outta me..if they died next I wouldn't lose sleep at night. (Keep in mind these are just my opinions-no bashing ;) )

Kate-PLEASE someone kill her off already..nuff said.
Jack-Literally went from hero to zero, having to answer to Sawyer (his former frenemy)'s just painful to watch.
Juliet-"Omg you looked at Kate, I'm gonna change my mind now"

On the other end of the spectrum, here are some that if they died would literally devastate me..

Desmond-I just think he's dashingly handsome, an all around good guy. I haven't seen any evil in him whatsoever, just a whole lotta charm. That Penelope is one lucky woman. (hence my username, lol)
Sayid-Ok, he might already be dead. We aren't 100% sure yet. But he's such a complex character, I can't bear to see him go.
Ben-Yeah yeah..I know. There are so many haters out there. But I'm a Ben supporter, and I think he has more answers than he's letting on. To lose him would be a major inconvenience I think.
Hurley-Now that would just be heartbreaking.