Make it web 2.0
The wordds "sportspiel.com.au" don't have to be the main aspect of the logo. That can be given underneath.
The logo will be used on my website, and also as my company logo, so it needs to pop. It needs to have two themes, sport and social media/digital technology.
I'd prefer you didn't use green as a primary colour, however as Australia's sporting colours are green and gold that's the only way I would see it working.
Kangaroos are not necessary :)
In terms of other colour schemes, I have no problem with a red,white and blue colour scheme, but feel free to come up with your own.
Have a bit of fun with it though! I'd rather not make it not be too corporate.