I think I've put my finger on why I have issues with Josephine's romance: Josephine herself seems to be mostly passive, and we don't let her not be.
In all the other romances I've done for Bioware games, the love interest has been an active participant in the romance. Liara and Leliana both flirt with you first, and Merrill comes to seek out Hawke at her house once her attraction has reached a certain height, but Josephine never does anything of the kind. She just eventually gives in to the Inquisitor's attention. Moreover, when she's engaged, Josephine tries to become active for a bit by calling it off (incidentally, that part was one of my favorite scenes because it at least showed how much the romance meant to her), but the Inquisitor completely preempts it by going behind her back for that duel. It feels like... Josephine is a marginalized and underused presence in her own romance.
I understand where you're coming from on Josephine, but I'm not sure I'd agree entirely. She is essentially passive through most of the romance... until the duel. Then, as I see it, she's quite active. She tracks you down to Val Royeaux to stop you from your mostly suicidal plan to duel with her suitor.
The thing is, Josephine's way of being active is really subtle. Look at the first scene we see her in Haven, with the noble. She's ostensibly in the background - but she controls the flow of the conversation to get what she wants out of it. She has three different ways of reigning in the noble depending on what you say, and makes it look like she's really just deferring to everyone around her. But when you watch the scene with all three dialogue options, she's not.
I think it's the same with the romance, once you've kick it off.