For that scenario to really work, Lee would have to have been affected differently by his father's neglect and his mother's supposed alcoholism. He grew up all 'truth, justice, and the Caprican way' but I know, from personal experience, that adult children do not always end up that way. Some of them are way beyond frakked up.

Writing it would mean writing Lee convincingly as a man who'd embraced a different set of values than the Lee we know did.

I don't think Kara was head-over-heels for Zak, but I do believe she loved him and took his affection at face value. If he'd been using her, she'd never have seen it coming, and if both boys had double-teamed her, so to speak, she would have been devastated by their betrayal. But at that particular moment in Kara's life, I think she was less suspicious/skeptical than she was as we got to know her.

Had it happened that way, she would never have let it happen again. She'd have gone the way of Helena Cain post-Gina-betrayal - cold, hard, unemotional, cruel.