Hmm, IIRC Chase's generic recommendations to people are Saya, Planetarian and Ever 17. You probably wouldn't like Planetarian though, as there's moe and airheadedness. Not sure about ever 17 though. Haven't played enough to form an opinion on it... Hmm... Maybe Fate/stay night?
There's degrees of airheadedness remember. Aki-chan is kind of like that, in a way, and she's my favourite character in recent times.