For Australians, even Australian founders, it's always worth looking at the E-3; this is even truer now that USCIS has said that under certain circumstances founders can get H-1B visas (and the E-3 is similar to the H-1B). The other options for Australian founders are the E-1 or E-2 treaty visa or the O-1 visa but these take a lot longer to prepare and are much more expensive than the E-3. But if you are inclined to explore the E-3 path as a founder, then absolutely consult with an attorney who has handled E-3s for founders (and there are lots of attorneys who handle visas for Australian founders).