NIW and LC both serves national interest in different ways. LC is the purpose to protect job opportunities fo American people, not for you. More work opportunities for you is not the purpose of NIW program. NIW progrm is to attract talented foreign people like you to serve US national interest, but not your interest. Granting you green card is the side effect of NIW program.
Again do not risk your GC application by using some naive excuses. One more naive excuse is to claim that applicant's H1B visa won't let you stay for long time or limit your job change.
Just for reference
Good luck