How about this... a far feched white elephant, but more realistic than Aussie running a CVF or Nimitz.
Another 1 (or 2 perhaps) LHD with more specific fixed wing capabilities (fuel and weapon bunkerage, some dedicated maintence for example). Say 75% as capable as the current LHD in amphibious operations if required. The additional fuel bunkerage may be useful as fleet oiler or for amphib helo operation etc.
Then a pool of 16 F-35B's, and several carrier based fixed wing UAV's (~20?). Not all would be deployed at the same time, and could be launched, recovered and refuelled off the regular LHD's. Now you are talking about 3 or 4 ships, of which you would have atleast one always avalible and most likely two. You could sustain 1 ship at all times, and two for a significant period. With four ships, you could surge all three (for a big international effort).
F-35B fitted with probes for a2a refuelling meaning they could operate 90%+ as the same missions as the F-35A's from land bases. But would be specifically useful over water, a broken probe or delayed/damaged refueller would not require the F-35B pilot to ditch in the ocean but land on a carrier. Aircraft could be forward based on the carrier. Aircraft could be refuelled and rearmed on the carrier. I would imagine landbased refuelling aircraft would operate over the carrier to extend flight time, range etc.
Cost of the carrier? Lets say a billion. Aircraft? lets say a billion. Crewing? It would be a big ask, yet achieveable, and could be crossed with the other LHD's.
And to get that carrier we would need atleast 1 more AWD more likely 2.
If we had:
12 subs with 8xTlam, 8xharpoon, 20xtorpedos
5 AWD's with SM-3, tlam, sm6, essm, laser phalanx
2 fully fitted LHD + 1 sealift (bay class?)
8 ANZAC II PAC3, tlam, sm6, essm, phalanx
20 OCV with Harpoon, Phanlax
14 patrol boats
30 NH90 RAN helos
6 LCAC + other landing craft
And Army who was fully equiped and 15% larger, a RAAF with 100 F-35A's already delivered and perhaps a few more refuellers and AWACs. And we had a pressing need for a carrier (ie US decline, rising regional powers).