Part of problem that this season may seem flat to some viewers is that there is no clearly defined purpose or goal for our main characters. The general goal in Season 1 was to survive and find a way off the island to get back to their off-island lives. The next seasons brought us stories of personal temptation and personal redemption. Now, in Season 6, there is no sense of total purpose.
A comparison of characters in Season 1 to present Season 6:
JACK
Season 1: a fixer of people, thrust into the leadership role by default with his "live together or die alone" speech.
Season 6: not a leader, a broken person following ghosts for no reason or purpose.
LOCKE
Season 1: a man with a second chance to get his life back in his survivalist dream.
Season 6: dead.
KATE
Season 1: a woman hiding her past, running away from her problems, with one goal to escape.
Season 6: bouncing back between Sawyer and Jack looking for a place to belong.
CLAIRE
Season 1: nervous expecting mother.
Season 6: zombie following Flocke.
HURLEY
Season 1: "unlucky" winner who felt cursed and crazy by the Numbers; a follower.
Season 6: a conduit for ghosts
SAYID
Season 1: on the verge of a new life with Nadia.
Season 6: zombie following Flocke
ROSE & BERNARD
Season 1: happy couple looking for peace.
Season 6: happy couple at peace in their island retirement.
JIN & SUN
Season 1: troubled married couple; Jin unhappy in job and Sun looking to flee marriage.
Season 6: separated married couple trying to get back together.
DESMOND
Season 1: Number pushing Swan station prisoner.
Season 6: drugged Package for Widmore
RICHARD
Season 1: advisor to the Others; Jacob's spokesman
Season 6: confused about events; now thrust into leadership role to stop Flocke.
BEN
Season 1: leader of the Others; murderer of his father.
Season 6: murderer of Jacob; follower of Ilana.
JULIET
Season 1: trying to get off island to return to her sister.
Season 6: dead.
Throughout the entire series, only Rose and Bernard seem to have found real purpose (and they have been written out to live happily ever after in retirement.) The rest of the characters (living) have been bogged down in an endless game of tag or follower the leader with no clue of why they are doing what they are doing.