The sky is the limit. A few things that come to mind..
Unless you have some really cool idea involving Aboriginal art, don't do it. Our target audience is any place on the entire globe, not just the Aboriginal people. We're inspired, not tunnel-visioned.
Also, unless you have some really cool idea involving the cross, Bible, or other blatant religious symbols, don't do those, either. We're plenty proud of our beliefs, but we believe in generating interest through example, not beating you upside the head with a Bible or screaming scripture at you. Besides, our target audience is already in our demographic.
Color scheme: Again, the sky is the limit. But the logo *MUST* be able to be delivered in white, black, blue, and other primary color backgrounds. It's going to be put onto letterhead for mailings, as well on a Joomla-type website. We don't have a theme selected yet so we need to the logo to work later on regardless of the final color scheme. The final logo would be delivered as several separate image files with different color backgrounds. This may be a no-brainer to you graphics people, but we wanted to mention it anyway.