Really bad. The ship’s only real strength is her speed. Ghost Ship is overpriced and sounds way better than it actually is. The ship is worth maybe 8-9 points. For example, HMS Nautilus is correctly priced (IMO) at 10 points, but far superior due to cannons and lower cost.
La Republique is actually better than LLG if you ask me. Not a great ship by any means, but a very unique support gunship in a deathmatch or larger game where your game isn’t dependent on her. LLG is 10 points more and doesn’t even have a clear role. Way too expensive as a gold runner, not enough cargo/combos to be a hybrid, and relatively weak cannons. Also, the Republique can be copied to max out Cursed dreadnought builds. The Delacroix is a far better 17 point French ship with 3 cargo to put a bunch of crew on.
I think the Corsairs are all about getting gold, mostly through exploring. I feel less incentive to board if I know I can’t eliminate a mast via ramming first. Not being pinned is nice, but the Corsairs also sometimes lack the size and Hoarding Gold type abilities that would make them a better boarding faction. I’ve always wondered why only 1 of their 4 masters got more than 4 cargo, while they have a bunch of 2 and 3 masters with 5 cargo.