Almost everyone I know uses a VPN these days, precisely because of this metadata retention law. All that fuckhead Brandis has achieved with his meglomaniac idiocy is sending the entire country underground. Good luck trying to profile everyone with a lack of metadata because of extensive VPN usage, that's most of the country now by the looks of things.
Notwithstanding all this, I'm already onto that possibility. I use a VPN service (Private Internet Access) for most of my browsing but I disable it when using my bank*, online grocery shopping and ordering food from EatNow. I also have a set of sites, such as the Bureau of Meteorology, ABC News and SmartTraveller that I regularly visit sans VPN, specifically to create an innocuous metadata trail for the spooks to hoover up. But all my politically incorrect commentary, and various other interests are all masked by VPN.
Likewise, I run two sets of emails; one lot "public" that I use for business, and another lot "private," hosted on my own server that I use for friends and family. Since said friends and family also have addresses on my server, and everyone connects to it via their VPNs, there's zero metadata (or even email interception or scanning) relating to emails passing through that server.
So I actually have quite a sizeable "metadata footprint" - enough that my VPN usage can be readily explained as business-related activity.
*My bank doesn't like PIA's VPN, as it complains and starts sending me warning SMSes about my account being hacked if I try to log in with the VPN active, so I have to use my bank without it.