Recommend a romantic plush hawaiian vacation for us?

My husband and I want to spend 5-7 days in Hawaii this August for the honeymoon we never had. Would also like to renew vows.We want to be near a nice beach and beautiful views and resort or villa. We don't really mind which island but I was doing a little preliminary research and loved Kauai for its lushness and romance. We want to stay under $400 a night in accomodations but we want something nice also. Can you please recommend something for us? We had originally booked something in the Caribbean (Barbados) during this time but will most likely be getting our money back because Hubby still does not have his green card and there's no telling when. He can only travel within the US currently. Thanks.