I get that the writers said they would stick wit hthe main thread of the show, which they did. It was Redemption and Atonement, by the way.
But they can't possibly pretend that the Island itself was almost a character on its own right. to let go of a opportunity to develop that was a waste of a good plot point. It sounds to me like they really were going to go for it, but lost their trail of thought halfway through.
Too many parallel plots with lossely defined connections might od that to you.
Despite that, there was a great quantity of memorable heartfelt acting and dialogue, and what a exercise on subtlety detection it was. It made me more aware of symbolic and psychological details in a narrative.
Love how the haters have very little to say about it despite a few poorly placed insults. Hate how the fans are the ones to blaim for it having so many haters.
Honestly, it would be easier to ignore a show you simply didn't care about if so many fans didn't make such a big deal about it.
But as the years go by, I believe the hate will subside and it will be remembered by its qualities. And it will be great, as long the critics don't forget that it had flaws too.
It sure as hell rose the bar for what quality writing in TV should be measured against (yeah, right... television will mostly suck, business as usual).