I do love this size ship. I haven't heard whether it is really faster than the Conny, Mercury and 600i. What's with that? Corsairs are typically fast, light ships that can't take a punch. Like a Corvette and I think they names may share etymology. So how fast is it?
We truly don't have statistics on it yet, but CIG is pegging it around the Connie - less missile, more gun but roughly equivalent firepower, speed, role. It would be a terrible ship to use as a heavy in combat. Treat it as a corvette, so hit fast, don't stick around unless you score big.
The other half of your question is something I did as a hobby, which was studying the Frankish influence in Europe. It's an example of how two words of similar origin can diverge, then converge again.
Corvette - comes from middle age French - old Dutch (was Lotharingia actually) - Corva meant small warship.
Corsare - Late middle ages French - Southern Frankish - Latin, but meant literally "Pirate boat"
Both terms have the same root: The latin term for "basket"