(I'm also considering using the unused Shipwrecker card model so that they can be put into the ship deck, but am currently undecided on that one.)
There was actually a discussion on Twitter the other day about Shipwreckers. I'm not sure which deck they are supposed to go into, but given the names and powers I'd say they go into the Pony deck, not Ship deck.
Would you be able to come up with a few lines to stick on our three misguided fillies?
It's a bit harder considering I have no idea what the final art was originally going to be and flavor texts usually relate to the art in some way. I'd imagine it was just them tearing up fanfics or ruining a story, but it could have been them destroying boats for all I know. Context would have been nice to know as well for why they are shipwrecking. Are they destroying bad fics about themselves? Are they trying to stop Twilight's reign of fanfiction terror? Do they just think it will be funny? It's hard to say what the original intent was. I'll assume the first one and spitball a bit:
Shorter one-liners assuming they're reacting to bad fics written about them:
Scootaloo: "Call me chicken will you?!"
Sweetie Belle: "I don't even like video games!" (You could add "Wait, what's a video game?" to the end of that also if you want.)
Apple Bloom: "I'm allergic to oranges!"
Quotes without ficlet titles are usually reserved for Twilight speaking, but I felt they were appropriate given the context of the cards and how they work. It's also a nice direct relation to what's probably going on in the art. Sets a nice precedent as well for any future Shipwreckers that are just "Shipwrecker NAME" with Ponies just destroying bad fics written about themselves.
I can come up with some longer or different ones if you'd like them.
EDIT: You mentioned there was unused art for these? I wasn't aware there was any official unused art for them.