Oz Working Holiday Visa

I'm hoping to travel with my wife to Canberra for 3-4 months where she'll be studying on a university exchange programme for 1 semester. I know I can apply for permission to work if I travel on her student (non-award) visa. However, I understand this would only allow me to work 20 hours a week, which probably won't be enough to pay the rent and bills.

My other main option is the Working Holiday Visa, since I'm under 30. However, I would want to work full-time for 3 months, out of the 3.5-4 months we're in Australia. On the requirements it keeps talking about "incidental" work, and "holiday" being the main component, so I'm just worried if I will be asked for evidence that I'll be travelling more than working.

Do you think I will encounter any problems if I apply for this visa and work for 3 months? Of course, our main reason for going to Oz is to see the place and travel around and get to know the country, but we would probably do lots of short weekend trips and a slightly longer trip over Easter, but I would aim to work the rest of the time.