I don't think that any ETS-member would have that little equipment with him/her then
the equipment you described in your post. At least a PSK and a decent knife/multitool.

Or do you mean a commercial instead of a private airplane?

Anyway, the life-raft can be used as a shelter, I see that there are no fire-starters,
so maybe use a piece of glass or make a fire-drill. Water and food can probably be found on the island.
I would also try to recover as much of plane wrechage (sp?) as possible.

And last, but not least, I would be ashamed that I wasn't better prepared and hope for the best!!