A couple things -
- All this debate over whether the writers did or didn't have things planned out, and whether that makes the proceedings legitimate or illegitimate are missing the point. The writers could have had every season arc plotted out and the show could suck, or the writers could leave things loose and open and it could be awesome.
So I don't understand the point of people saying "THEY HAD IT ALL PLANNED! VINDICATED!"
At the end of the day, whether it is planned or made up on the fly, it needs to be entertaining, compelling television. And it was.
- Regarding the mysteries, for me, the fun of LOST's mysteries was chewing the fat over them, and guessing about them. The fun has never been finding out the truth. The truth is almost always incidental. Right from the Pilot, it has been "OH SHIT looping French transmission!" "OH SHIT Sayeed found some crazy rope/cable running into the Ocean" "OH SHIT they are in the arctic now!"
Half the fun of LOST is just waiting for "WE HAVE TO MOVE THE ISLAND" moments.
The answers are not as much fun as the questions. I'm shocked this has to be explained to people. How often when you were little (or maybe as an adult) have you been excited about a Christmas present sitting under the tree? SO EXCITED to open it... thinking about it for weeks. Then when the moment comes and you do open it, even if it's a sweet gift, it can't match that anticipation.
Ditto for the anticipation over sex with a new partner, anticipation over playing a new game you've been hyped about, etc.
For me LOST was an "Oh shit POLAR BEARS!" show and I basically didn't care where they came from, as long as the show didn't end up being completely random (and it didn't).
There is a pretty reasonable framework/mythology that the show hung all its "polar bear" moments on, and that is enough for me.