DON'T READ THIS IF YOU HAVEN'T SEEN THE LOSTFINALE AND WANT TO!
To say I'm a fan of LOST would be an understatement.
My initial response to the finale was... "The first 2 hours and 15 minutes were unbelievable. The last 30 seconds were a perfect ending. The 14 minutes and 30 seconds between were the part that many will not like. I'm still not sure what I think of the entire church scene. "
24 hours later, I find myself in a different position, with much more clarity (but not total clarity... I don't think that was Lindelhoff/Carlton's goal with the finale)
Here's my quick explanation/understanding...
Flashbacks, Flash Forwards, Island Time, 1977 experiences were all "real life" experiences. The Flash Sideways we've been seeing this season were a sort of "purgatory" where they went to when dead. As Christian Shepherd said in his conversation with Jack, the time of death in "real time" was irrelevant to Flash Sideways.
Whenever you die, you take up your "Island Form" in the Flash Sideways.... See More
They carry on in their flash sideways until they come in touch with some sort of catalyst that would reveal their life to them. For most of them, it took a contact with their one true love. Upon those touch moments, they remembered everything all the way up to their death.
So, Sawyer could have lived to 70 after getting off the island on Aijira flight. Hurley and Ben definitely lived on... Hurley as the new "Jacob" & Ben as his number two (hence the line to Ben outside the church, "You made a great #2"). Or Kate likely had a decent life after the island (her line to Jack in Flash Sideways, "I've missed you", I think in reference to her time away from Jack after leaving the Island on the plane with Lapidas, etc.)
As far as Ana Lucia, Miles, and others... Desmond (the Constant) made mention when Hurley asked about Ana Lucia that she wasn't ready yet... like there was something she still needed to do in the Flash Sideways before "crossing over".
Ben chose not to go. Eloise asked Desmond not to take Daniel because, although she knew of everything going on in Flashsideways world, she wanted to simply enjoy being with the son she had killed.
The flash of light in the church symbolized those heading into "the light" (cross reference light on the island). My real question, which I believe the creators wanted to leave open, was whether they were going to "heaven" or back to the island.
The more removed I get from it, I really liked it all. It was a good way to end.