Well...I’m no Chester Nimitz, but I’ve never heard of a fight where someone said “We brought too many guns!” If we end up fighting a war against people who build islands out of dredged up sand don’t most of you imagine there will be plenty of “niche” shooting to do?
That's generally true but there are better ways to spend money on weapons systems for the -60. Without a good sighting system and stuck on the stub wing of a helicopter like that, that gun kinda sprays, like trying to accurately shoot an AK-47 from the hip. The volume of fire is certainly one of the positives (I'm not being sarcastic by saying this).
(And not that I think the navalized Hellfire would be that much more accurate in real world engagements against a swarm of small boats... just my opinion.)