The thing with building is, unless you live with someone for free, you have to pay rent as well as a mortage while the house gets built - at least 7 months. There are so many costs associated with building that people don't realise (I work for a building company). You don't just pay for the house model, there's all sorts of shire fees etc that can add up.

We ummed and aaahed about building vs buying established, and have gone established. Not a long term home (less than 5 years) but we got 30kms CLOSER to CBD on a much, much larger block for the same price we'd have got building. If you're thinking long term and value, IMO established closer to CBD is better - as it gets rezoned for development the land sells for a crapload.

I personally wouldn't buy/build just because of the increase in government assistance. If you were going to anyway then bonus for you!