Next arc might finally be the arc where we get the long-awaited Cai art. What kind of art do you guys expect out of this? Might be Wood-related honestly (since Wood is really common in Emerald Seas), though I don't exactly know what function it will serve in our build. Hopefully it would be a Stealth art (though I wouldn't hold my breath for it).
I think that there is going to be a selection of arts from which to choose from. Here is the quote that gives us the most amount of information IC about the arts.
"I promised benefits and I will not break my word," the other girl replied seriously. "I have also instructed the head of the Cai families archive to search out arts which may suit your inclinations. That may take some time to complete, and the results will be limited… I may only take so much of the head archivist's time and resources."
The key here, I believe, is the word limited. We don't know exactly what limited means in this context but my guess is more than one less than four. More than one simply because Cai refers to the request as a search for "arts" which indicates more than 1 art. Less than four because we get about 4 arts per search in the archives and that's us dedicated to the task. The Head Librarian will have more skill than us in searching libraries but will have less time, interest, and knowledge of what we like. Which, in my mind, makes the vastly superior skill kind of a wash.
What those arts may be, however, is hinted at with the phrase "may suit your inclination." The first thing to note is that it is not guaranteed to suit our inclination, and the second thing to note is that the word inclination is fairly broad. These arts are unlikely to be niche in their uses but more broadly applicable to what we may like to pursue. My guess, given when these instructions were given, is that there is going to be a general purpose stealth art, a music art (perhaps a social music art? I'm not certain), and possibly a general purpose dodge/defense art (this due to our discussion with Cai in the outer sect about our preference to dodge and take hits.)
I'm more confident about the stealth art and the music art as those would fit with our inclinations when Cai sent the request. I'm less sure about the defense art and it may be a perception art given Cai's desire at the time to be someone more focused on information gathering.
Eitherway, I'm excited to see what arts may or may not be coming up!