I would like to see once, just once a romance for male players where a female character has a dead husband/lover or a living son from another man. It could be an interesting story which leaves a lot of room for content. I doubt they will ever dare to do it though as it will never sell well.
(not being evil to male players, more for science)
Cassandra mentions her dead boyfriend, and just after sex lol....
That did me absolutely nothing. That meant she trusted me enough to tell me her story. I am aware that female characters could have past relationships before my character, even when they don't mention it. I always dated girls who had already boyfriends before me, as many folks I suppose, I don't see how It could affect me in a video game. But, anyway there will be always people offended for something.
As far as I am concerned, I'd love Bioware giving us instead an angst romance with a woman who had a dead husband in DAI, and replacing the dysney romance with Josephine. 
Don't get me wrong, I like her, the romance was sweet. But I would lie if I told that it affected me. I was totally indifferent, and some things bothered me. I never asked for a dysney romance, and I am kinda bummed that such thing was created in Dragon age. I'd even dare to claim that women are much more interested by this kind of thing than men overall. ( maybe I am wrong, but from my experience from real life, I truly believe it )
The romance with Josephine was infortunately boring, it lacked drama, tension, angst, I don't know, it was too sweet or perfect, with cheesy lines, and several times I felt that this romance didn't belong to dragon age. ( no offense to those who loved the romance with Josephine, this is just my opinion ) And I don't get why Josephine lifts her foot while she is kissing my character, ( I can't help but think that it was ridiculous the two time I saw it )
The dual for her was cheesy, where we have to declare our love for her in front of everyone, like a prince to her princess. Didn't like it. I must headcanon the whole thing, to make it less dysney, and more dragon age. You could be romantic, have a romantic cutescene without turning the whole thing into something that gave me the vibe of a dysney anime. 
I have seen on internet a lot more men complaining about Josephine and who think that her romance was boring, than female players, who find her content absolutely sweet on the opposite. I found it interesting. ( at least from what I have seen, and i'm not saying that it is case for everyone, not at all. Just a trend that straight males seem less happy or less impressed. )
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For Thane, it was said that he was going to die, so people who conscientiously chose to be with him, should have expected that he wouldn't live long enough. But I admit that Bioware shouldn't have killed Thane thanks to Kai Leng, it was better to let Thane live in M3, and finally a few years after the ending, a natural path like it was implied and explained in M2. It didn't need more drama.