Yeah, Onas pulses are great. Yeah, Carriers and Heavy Destroyers both need escorts (though Carriers need them more obviously). However here are my views on the Salrilian and Audemedon Carriers:
Salrilian Carrier: Hardest Carrier to fight against when you're the one fighting it, even in a Heavy Destroyer. The reason for this is that the T-Space Bolt Rod's range is almost as long as that of the primary weapon's range on a HVD. (It's slightly shorter because of the Carrier's large sprite.) Those Magno Pulses are pretty nasty, too. It's the second-best to actually fly in, because the computer's AI for ships will send them straight towards you, directly in the path of the beam. Unfortunately the beam doesn't have three-way power like the Trazer does.
Audemedon Carrier: Second-hardest Carrier to fight against. In a HVD, a human pilot with any skill should have no problem at all staying out of range of the Trazer, and will just blast it with its primary weapon. The problems will be (of course) those nastly little Audemedon fighters and its escorts, if any. And missiles, but those don't fire very rapidly. It's the best carrier to actually fly in, and can take on whole fleets pretty well. The beam is VERY powerful and goes three ways, the fighters are even_better than the Salrilian ones, and the missiles are good support. Regardless, it still needs escorts if it's gonna take on a crowd of Gunships.
And only pilot HVD's yourself, the computer will get them destroyed. Take care of your Heavy Destroyer!!
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--Joolzman5, that guy with the red spikey hair