When's the last time you saw an unkindness of ravens?

They're also not terribly scattered, what with having the mecha Tortuga on Shard 31.

And, sure, you can make a pirate who calls himself something else because he thinks Raven is a stupid name. But you don't get to change the setting. They've been named ravens because they started as scavengers. They could have been named worse, like Vultures.