I don't actually mind that much
. I'm fairly certain I won't hear every conversation, and I'll probably end up using the wiki to read some.
Ah. Well, fine then. Yes, you can talk to Loghain about the slavery. From his perspective, he mentions how Ferelden's coffers are nearly empty, as a result of the Civil War, all the banns and arls arming as many men as they can, gathering supplies and killing each other. Even though he pretty much won the civil war (based on the gossipers as the game progresses) Ferelden no longer had the money or the supplies available to fight the darkspawn.
Tevinter made an offer, and payed exorbitant amounts for access to the alienage, and Loghain agreed so he could defend Ferelden.
What he does is most certainly not moral in any way, but he does stand behind his reasons. Ferelden wouldn't be able to supply itself had he not made that deal. He's upset that the Warden stopped it. Whether it's justifiable or not, I'm not going to touch, but if you bring it up during the Landsmeet, that is also the reason he gives for allowing it to happen.
I think Xil is upset that she can't outright blame him and that he doesn't take responsibility for it, and there is a darn good reason why she can feel that way. When I first spoke with him over the issue, I was also quite upset.
I think he does take responsibility for what he does, but he won't apologize for doing something he feels is necessary. That's what I make of him.