Cleolinda everywhere

I think: Because their time on the Island was so important, they all needed to reconnect and resolve their issues before they could move on to Heaven-or-whatever. So sideways was the mutually constructed world where everyone went when they died, whenever they died, on the Island or later, even years later. Whenever anyone from that group died, their consciousness immediately went back to flight 815 until and lived through that until they got their collective shit together.

I'm still not sure about that part, but I like how the actual on-Island stuff resolved. Except Jack didn't say the words for Hurley, that confused me. Maybe he thought them.