The Inquisitor would not have read Asunder so it should not any difference to anyone who roleplays.
The Inquisitor wouldn't, but the real person playing him might. Everyone should play the game the way they like, but I'm still curious about possible in-universe rationalizations instead of the same "Cole is a psycho serial killer!" or "Cole is a traumatized merciful spirit" discussion.
Some ideas, for example:
-A Dwarf Inquisitor may be positive since Dwarves don't care so much about the Fade and its inhabitants. Or the opposite, the Fade is so strange for them that he or she won't like an unknown near them.
-Normally the Dalish don't even like the Spirit School of magic, so maybe a Dalish Inquisitor would be totally opposed to Cole. Or maybe the Dalish Inquisitor is a free spirit like Merrill in that regard.
- A human mage could be like Rhys, seeing a mystery to unveil and a soul in need of help. Or they could be like Lambert, convinced that the only good demon is the dead demon and that any negotiation means risking possession.