In my eyes, Lord Asriel was everything that a by-the-side hero could hope to be- strong, brave, intelligent, daring- and yet his role seemed to hint at various acts of malicious intent. However, his final sacrifice, which I won't go into here for those of you who have not read the books, deemed him worthy of a place atop the hero pedestal, and his obvious love for his daughter, although somewhat suppressed, has led me to believe that this power-hungry leader was not as unrightuous as he first appears.
I don't know whether Lyra would blme him for Roger's demise, or the tumult that is causing the worlds to tumble under a reign of foreign havoc, growing as she does and learning that most of her journey seemed to have been placed before her by higher powers. She seems to take it in her stride and confront the evils that throw themselves at her as she goes along, but Pullman never really explains exactly how she feels about her father- whether she forgave him, or evn whether she blamed him at all. Does this make Asriel innocent? Or maybe, Lyra forgiving? Or just oblivious?
As I have mentioned, Asriel is definately capable of some sort of love, as he demonstrates with Mrs. Coulter on a couple of occasions, and the fact that he saved Lyra from Mrs. Coulter's late (by Asriel's hand) husband. I am unsure as to whether Asriel was affected by what he was doing to the worlds- maybe he realised that his daughter's safety was significantly more important to him, and to the fate of existence- but it is evident that his reasons for sacrificing everything to save Lyra must have had inititave based on the fact that he still cared for his feisty daughter, so much like her father, and was willing to go to the necessary means to protect her.
Obviously this is not a decision made lightly.