What Makes a Good Romantic Hero?

I finished A Difference of Opinion by Nancy Dane last night. This morning, I woke up thinking about it, particularly about the hero, Allen Matthers. I'm not quite sure what to think about him. On the one hand, he's a very appealing character; on the other, [SPOILER] he's a murderer.

Allen has a lot of the qualities that I find attractive in a romantic lead, without falling into the cliche' of the romance-novel hero. It's clear that Allen is muscular and strong, but there are no descriptions of his "v-shaped back" or his "muscular thighs." He's handsome, with his bright blue eyes and coppery hair. He's intelligent and he's a musician, facts that raise him above his humble mountain roots. He's very good to Nelda, always showing up when she's in desperate circumstances, saving her life on more than one occasion. And he's always the gentleman - even when they are traveling together at the end of the story and camping alone together, he makes no move to push himself on Nelda. I liked the way he was openly confident he and Nelda would be together, even when she was telling herself she hated him for being a traitor.

But....I can't forget that Allen Matthers killed two men over a pocket watch and some gold coins. I suppose you could argue he killed them because they were a threat to his life - one of them had already shot Nelda. But Allen had already disabled one of the men by breaking his arm - why slit his throat as well? The story happens in a very violent time, the American Civil War. There are hints throughout the book that Allen may have killed several other men in the course of his work with the army (he's a "scout," not a soldier, though). I don't know. I may be able eventually to talk myself into believing he HAD to do it, but right now, it just seems to put a stain on his character that is hard to look past. It's like Allen Matthers, along with Joey Bolitho from FJ Warren's Broken Bonds, will always have an asterisk after his name in the "Hall of Fame" of romantic heroes I've encountered in my reading, ha ha.