I think its pretty obvious that the island will not let Ben die....
and I really think its obvious that Ben needed Sayid to comeback....thats why he was so concerned when Sayid walked away at the docks....
This may also explain why Tom shot into the sand instead of killing Sayid, Jin & Benard at the beach....
Why JUliet was brought to the island, cuz according to that one chick "she looks exactly like her"....
I think Ben knew the whole time, who he had to keep alive.....he just didnt know how everything would unfold....
The only thing that kills this theory is that they did try to shoot/kill Sawyer&Jin when they were on the raft.....
Plus remeber Bens story about the resurrection....i thought he was talkin about Locke/Jacob...but maybe he was talkin about himself....
Lil Ben was losing faith/patience....he just wanted to join the hostiles, even though it wasnt yet his time....his death/resurrection restored his faith to be patient and wait like Richard told him too....