As for F/A-18E/F or F-15T, I would lean towards the Super Hornet. Ok, so it doesn't have the speed or the grunt of an F-15, but it does have alot of growth left in it, is already (or about to be) fully networked, has a higher performance AESA radar with more improvements coming (electronic attack etc), is already baselined with all our current and projected weapons systems (except AGM-142), and we can easily plug in to the US Navy's production and support system (as we did with the classic Hornets). Another plus is Boeing already has substantial support facilities already established in-country at Amberley and W'Town.
The biggest advantage to the F15T/SG/E is that apart from the AESA radar, everything else (EP,EA, Networked, weapon commonality) are current, proven and operationally successful systems. To plug into US Navy's production and support should be just as easy as plugging into the USAF's (probably easier as any base down range that the RAAF may find themselves in will have a greater probability of having a USAF unit rather than a USN unit stationed there). Other advantages include the greater range and larger radar dish offered. (not to mention the fact that AGM-142 is also not supported...)
Boeing also makes the F15 so the support facilities already established are just as much as a plus as for the super hornet.
The only disadvantage to selecting an F15 over a Super Hornet is that the aircrew will need complete re-training and a new OCU would need to be stood up, otherwise, bring on the strike eagle!