Should Kieran play a major role in the next Dragon Age? (Spoiler)

It's seem to me that you aren't eager to accept what the truth is.

Those banters aren't a proof,if the warden start a romance without never having sex with a LI(which is a legit path totally respected in DAO)they are not going  to sleep with them off-screen wihtout the input of the player.That is proved by the fact that the child named Kieran is never mentioned to be in existence in WH in the case of a Warden who never slept with Morrigan despite having triggered the romance with her.

My position has never been that a warden who's romance never progresses to a sexual one has their character having sex off screen. My point was that someone who's relationship progresses to the sexual stage and yet they only personally select the option to sleep with your LI once does have the implication that their character continues to sleep with their LI more than just the one time so long as their relationship is active. 

Your position was that a human Kieran cannot possibly exist because Morrigan's romance can begin as early as Lothering and the game takes place over to long of a period for the child to be conceived at that point and Morrigan not be showing by the end of the game. My position is that is only true if you assume that the only time the Warden sleeps with Morrigan is at the first possible opportunity and never again, and that if you sleep with a LI once, the game presumes you continue to do so.

My position has never been that human Kieran is possible if a Warden romances Morrigan and never sleeps with her, period.