On the ASIA server, you can get two captains – Iona and Kirishima – with 10 skill points each, and you get them just by logging in. That’s all! They’re just for Arpeggio ships, though, so if you don’t use those I’m not sure if you have any use for these two free captains.
Also, I somehow doubt this is going to come to NA or EU; I’d like to see more missions, personally, but who knows when we might get more. There are still a few Arpeggio ships NA hasn’t had yet, for example, like the rest of the Myoko sisters.