Basically, the Others should be very afraid if Locke finds his way past the security gate shown in commercials for the next episode.

I think you may be onto something here, Locke is a man of faith, but he puts his faith in the hands of others(maybe literally) whereas Eko was really just glued to his own faith. No doubt the island tried to turn eko into a locke type character, knew that couldn't happen, and wiped him out... is that what you are getting at?