Yes, that form of dress will be fine. Usually, the only things they MAY frown on would be jeans, and NO shorts in the dining room. Those are fine for the Windjammer buffett on deck #11. I am one who doesn't even own a suit, sport jacket, or a tie, and nice slacks and a golf shirt, polo, etc., are perfectly fine, even for the formal nights. You're on vacation!! Allow youself, within reason, to have a great time!!