I agree. I loved the angst that the potential Amell/Cullen storyline could have told. Don't get me wrong, I love the Inquisitor romance. But it was a little too sugary sweet for my tastes. I like the star-crossed lovers aspect a lot because it sets the tone for angst and tragedy, which makes a story much more compelling. Is that awful for me to say? That I prefer stories that invoke misery? LoL. Not misery so much, but raw bittersweet emotion.
So that one will always be my wistful what could have been. But of course I like the Inquisitor romance because, well, I got to FINALLY romance Cullen.
Aww hahaha, I actually imagined it to be far, far more cheerful and happy in my head. The way I saw it, Amell and Cullen were kept apart due to societal constructs and restrictions that were out of their control. Things went bad, but that's the way fate meant it to happen. Now, in Inquisition, we are literally tearing down the very foundations of those constructs in the first place. We're advocating change, reform - we have mages, Templars, Qunari, elves, the traditionally oppressed and the traditional oppressors, all fighting under one banner. We're defying the fates that the gods had assigned to us generations ago, and since I have the power to bend reality and time in my bare hand I figure I'm well within my rights to imagine that the barriers of fate that kept my Amell's kind and gentle soul from being with Cullen's kind and gentle soul can be torn down as well. Oops, my sunshiny optimism is showing. LOL. Sorry.
But yeah, that's just how I'm comfortable headcanoning it. But I have to agree that I don't think Cullen was going to ask about Surana/Amell's romance with Leliana. I think he just felt guilty about how he treated her, and that doesn't mean he still has to be infatuated with her. Cullen's always been rather gentlemanly, and it probably doesn't sit well with him that he wasn't able to apologize for a mistake he made. Maybe he's even worried that Leliana thinks poorly of him because of something Amell might have said. You can prob look at Leliana's jests as a lighthearted way of reassuring him that Amell didn't hold any grudges.