I was just thinking about what Richard would be doing in the FS, and where he would be. If the island sank in 1977, one would assume that he is dead in the FS since he was on the island the day the bomb went off. However, he is the only one that is alive on the island now, but is also dead on the island in the FS (aside from Jacob and Flocke possibly). This could actually push for a fun plot line. For instance, can someone who dies in another timeline on the island still be able to be seen by Hurley? If so, dead Alt-Richard can maybe show up and speak to Hurley similar to Michael and Richard's wife. Or maybe Richard is actually dead and that is why he doesn't age (a "Sixth Sense" sort of thing).
Another possibility is that the boy that Flocke keeps seeing is from the FS. Maybe this is Jacob (or whoever it may be) from the FS.
I don't know, this doesn't make much sense and I really have little evidence for any of this. Just trying to think outside the box. Anyone want to add to these ideas?