Here's an idea that might help you guys down-under, or anywhere else where you don't get enough power to pull you up the hills. I'm not advocating that you should break any laws, but, if you do want to then this idea should stop you from getting caught.
Checkout the Speedict controller interface. It goes between your battery and controller and displays and is set on an Android phone. You can program it to comply with your local legal regulations by limiting the speed and current with its various governor settings. All the settings can be ungoverned by pressing a single switch on your phone.
So you make the governor settings to comply and then switch off the governor and ride around with whatever power you want without making it too obvious, so ability to air pedal is a pre-requisite. If your bike with massive motor and battery is noticed by police and they stop you, you tell them it's gutless because of the draconian laws with which you have to comply, and you invite them to have a go on it. While, they're getting ready, you switch on the governor from your phone, and after trying it they ask, " How come you could go so fast on such a low powered bike?", so you tell them that you can pedal very hard. It helps if you're panting a bit when they first stop you. Never in a million years (unless they read this) will they figure out or be able to prove that you changed something. The only incriminating evidence is the included data-logger, which they might be able to figure out, but, if they decide to take the bike away for further investigation, you leave the bike switched on, and all the data will be overwritten before they figure out how to get it out, or, if you have time, while they're loading up you bike, you can manually delete all the files from your phone. http://www.speedict.com/
The main risk would be that you had an accident and were incapacitated so unable to operate your phone. Then you'll take a bit of a dive.