I thought the MAD capability was removed because of weight. Also the APU is in that area of the ac.
There are no tactical requirements which drive you to high level ASW. In fact it just increases the problems. Most ASW Sensors, at high level, will be degraded. The USN MPA radars have never been great compared to SEARCHWATER.
GPS guided sonobuoys, $800 a pop just for the basic types, wings on weapons etc all technically possible but just add expense and additional things to go wrong both technically and tactically.
The reasons for HLASW must be one or all, in varying degrees, of the following:
Ac performance.
Ac fatigue.
Other simultaneously tasked mission.