Oh, I think Ashya will absolutely love Signy! I can imagine them trading questions and answers well into the small hours of the morning. Not to mention that Signy is somewhat of a living legend...a dwarven mage! How does she do it? Does she keep a steady supply of lyrium to dose herself regularly? (Careful, hide it from the templars, they'll steal it for themselves!) Did she go through the Harrowing too? She has never been guarded by templars?
Yes, I can see them getting along quite, quite well.