The reason why the F4 go and not the muscle is just like the game of chess. Weaker pieces go first to set up the opponents strong pieces. That way when you are ready to attack, you have the advantage.

I believe that the 3.2 million Miles asked for is some sort of reference to the important people on the boat that Ben wants dead. For example, 3 people are dead and there are 2 more to go.

Miles knows about Michael because of his powers. There is a ghost (Ana-Lucia?) following him and told Miles what his name really is.

The conversation between Michael and Frank was not just a coincidence. I am sure that there is a file with pictures of all the people on the flight. Maybe someone recognized him and they are working him until they can use him against Ben.

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