Most likely yes, friend. Companions are meant to be continuously expanded throughout the games development. Her writer is Savin, who's also the lead dev, and while I do not know his specific plans, I'm sure there will be plenty more content for her in the future.
Yes. As Savin's said before, pretty much anything can get additional content up to the end of development. On general principle, as a companion Arona's going to get more stuff as the main story does because that's how companions work. There's also the statement in that post that Arona specifically has some things planned as part of learning to lead.
