Forum:New game plus?

I've been wondering about the New Game Plus feature. I have just finished the trilogy playing straight through, but is there a way to play from 1 to 2 to 3 with the new game plus for each? Or do you have to play through 1, then import to 1 again and finish again, then import to 2 and play through, then import to 2 and finish again?

Also are the enemies harder in new game plus for each game?

Thanks very much in advance.