We are a retired couple, but still pretty active. We chose this January cruise because we wanted summer weather in the middle of our US winter, and because the dates were just right for us. Australia and New Zealand were interesting, and we had a great time doing a lot of walking and hiking. We are not much into the excursions that involve a long bus ride, although some riding in buses is inevitable. So without trying to say what is good or bad, here are a few facts that may be relevant to you.
1. The airplane ride from the US is a long one. 15 hours from LAX Sydney. But we payed the extra $150 for extra leg room on the American flight US to Sydney. They fed us well, there are plenty of movies to choose from, and with noise cancelling headphones you can listen the movies or music without having to crank up the volume. So having set our minds to it, and planning when we would sleep, it was OK. We returned on Qantas on an Airbus A-380, the world's largest airliner.. Even in coach, the seats are wide and there is reasonable leg room.
2. We arrived in Sydney and spent two nights at the Harbour Rocks Hotel, a little boutique hotel 10 minute walk from the ship terminal, the train station (we rode the train from the airport -- easy), excellent buffet breakfast, and reasonably priced. Got opera tickets well in advance. Good opera at the iconic opera house, which is also a short walk from the hotel. Enjoyed a couple of ferry rides on our Opel Card (a good deal.) You can check out interesting things like the Botanical Gardens, a ferry ride to Manly Beach ( a little beach town catering to tourists with a mile or two of boardwalk along wide sandy beaches), Luna Park (an old fashioned amusement park with no admission fee), a walk across the bridge, the bustling central business district, etc.
Small but clean and functional. (This review made my select a cabin category. So I picked one at random, I have no idea what is was other than it was a balcony on the Aloha deck, mid ship.