Chinese history and culture is one of the richest and certainly the oldest (4000 years) in the world. Its influence in culture can be seen in many Asian countries, such as Japan, Korea, Vietnam, etc.
Being able to speak Mandarin will help if your future career is in business, as China has become the second largest economy in the world and the top trade partner of New Zealand. Moreover, Chinese is also the most widely spoken language in the world (1.2 billion, 1/5 of the world population), and New Zealand has a large Chinese community and large numbers of Chinese tourists every year.
With the oral language sounding like music and the written language looking like drawings, learning Mandarin trains both sides of the brain. Lastly, learning Mandarin is easier than you think! There are no plurals, no tenses, no subject-verb agreement, and no conjugations! All the technical words in mathematics, science, law, and medical are readily understood by most native speakers.