Glorious! Color me a fan. Not only does Cia now have one costume for each of Link's typical colors, with the blonde hair it's also a reference to Pirate Aryll, which goes hand in hand with Lana's new recolor costume, which is based on Outset Aryll. That's very fitting, both cosplaying as Link's sister.
The Master Wind Waker Map offers a total of 16 recolor costumes. That's the same number of costumes that the DLC Adventure Maps on the Wii U had and I suppose that Koei Tecmo is simply keeping the same value up. It's still a shame that certain characters got left out. The ones, who apparently didn't get a new costume are Impa, Ganondorf, Agitha, Zant, Wizzro, Young Link, Linkle, Skull Kid and Medli.
Especially the last four seem disappointing, because the DLC and Legends characters only have gotten one costume so far, on the Great Sea Map. Medli doesn't even have a single costume yet and at least the adorable bird girl should have gotten one costume here, though it still might be that the Rewards Map has one for her.
They might have dodged a bullet, though. Those recolor costumes can be a mixed bag. Some of them look great, others are just absolutely hideous. Especially Twili Midna got blemished twice now. There's no value in these costumes, if they look bad. (You can find pictures of all new costumes in Koei Wiki, if you want to take a look.)
But I'm quite happy with Cia's collection so far. The only one that I don't like is her Master Quest costume in Link's colors. I get the idea, but it doesn't look good. But I really liked the blue Lana and the green Manhandla recolors. And in Legends I finally got my red recolor costume for her, as well as the nice blonde / purple Aryll one. The only other Cia recolor that I would like to see is some white Fierce Deity costume. And with the Link's Awakening Pack a Marin recolor for both Lana and Cia would be lovely, since she's basically one of Link's oldest love interests. And now that I think about it, they should also get a Zelda recolor at some point...