SCALE OF NICENESS

Keep in mind that the true measure of an individual is how he treats a person who can do him absolutely no good. — Ann Landers

 There were many Machiavellian characters on LOST. But who was the "nicest?"
Different people may have different definitions or parameters for the term "nice."
The dictionary defines the term as:

1.  pleasant; agreeable; satisfactory;  (of a person) pleasant in manner; good-natured; kind: he's a really nice guy.
2.  fine or subtle: a nice distinction;  requiring careful thought or attention: a nice point.
3.  archaic term:  fastidious; scrupulous (very attentive to details).

Nice is more a middle of the road, nonconfrontational, safe person to be around.

Under definition number 1, most people would say Hurley would be the nicest. He was always respectful to other people's thoughts or opinions. He was not judgmental. He had an easy going outlook on island life. He kept his own issues hidden as to not burden his friends with his problems. He was good natured and kind.

Under definition number 2, Jack may be a choice because at times he dwelled on the fine points of a situation. He was detail oriented in a calm way.  He did not like to go half-cocked into the jungle without first making certain of the details of any plan. 

Under definition number 3, the most scrupulous, anal-retentive person on details had to be Ben. Most people would not consider Ben a "nice person," but he was a nice villain. There were a few other characters who bent toward detail analysis such as Artz, who started science projects on the beach (including toxic spiders) to the lecturing on the instability of explosives (which led to his demise.)

On the other side of the scale, Sawyer was probably the least pleasant of the main characters. He was irritable, got under other people's skin, rude, crude, snarky and rarely thought of the group ahead of himself. Kate was a pleasant person to be around, but she had a cold distance that made it difficult to make friends or trust other people. Sayid also had a cold dispassion about him that made many character uncomfortable around him. Part of this could have been stereotypical prejudice; part of it could be that others viewed him as a dangerous person capable of harm.

NICE SCALE
NICEST                                                                                                                       LEAST NICE 
Hurley * Frank * Bernard * Libby * Rose * Jack * Claire * Charlie * Kate * Sawyer * Ben

It appears that being "nice" was not the key to salvation from the Island.
Both Hurley and Ben wound up on the doorstep of the after life church. Together.
Frank, Claire, Kate and Sawyer all made it off the island on the Ajira plane.