She's standoffish so it won't be readily apparent, but this answer does endear him to her.

"Okay," she says, adding, "Appreciate it," like it's an afterthought. She probably will come to chat with him in person, though it won't be on Astarion's recommendation thanks.

"I'd better let you go." Except that it's a clear dismissal, because she has a lot to process, and she'd like to do that off the training grounds where she'll only distract herself with her mace and some unlucky target.