I think another one of my problems is that I feel like the text wants me to feel sorry for him...and I don't.

It's just that he's finally outgrown his more petty and selfish qualities.

I wish they'd shown how and why, though. Spike's transformation makes complete sense. Buffy's does as well. Some of the weaknesses of the Dark Willow stuff aside, Willow's fall to darkness? Yeah, makes total sense. But I just don't see an arc for Xander.