thats not the command vision at all for any RAN force including the LHA;s within the force construct.
My thinking when suggesting Melbourne and Newcastle for possible conversion in to task force command ships was that they are US designed ships so would likely be compatable with the US sourced systems salvaged from the LHAs, they have recently been extensively upgraded and life extended and with the Mk13 suppressed would have a significant amount of volume freed up for command spaces. They will also be surplus to requirements (as FFGs) upon the delivery of the AWDs.
It wasn't a cunning plan or strategy on my part to usurp the LHDs, rather a what do we have, what can we use it for. I don't know what the conops are but I was assuming that a smaller platform with command capability would / could be useful in situations where the deployment of a purple asset such as an LHD was unviable, unnecessary, unwise, uneconomical etc. Say West Africa, Persian Gulf, North Korea etc. Not so much a purple asset as a destroyer leader with additional command, comms etc and of course space for the commander, their staff and maybe some extras such as intelligence, linguists, AFP? etc depending on the actual task at hand.
The eventual replacement for such a platform would be something along the lines of the Danish Absalon. Like I said I am not privy to what is planned and why but it just seems to be a practical sort of capability to have.
A big issue with using a platform such as the AWD as a command ship is the sometimes incompatability between comms and radars, think HMS Sheffield, you can't afford to be without either your groups primary coms or radar so you put them on seperate platforms.