I think Bearded Warden being Stroud would be neat. A minor character returning as a companion has already been shown as possible with Isabela as well.
Explain how there would be an old god baby if you didn't do the ritual. And explain why morrigan would offer it to you at all if she could just do it willy nilly without your help.
Also explain why they would bother making the inquisitor the OGB. Like..what would be the earthly point? Why bother making a confirmed male human child who would be only ten years old jump through a bunch of hoops to suddenly become either an elf or qunari or woman.
Not to mention they've confirmed that the elven inquisitor is dalish and I'm pretty dang sure Morrigan was not allowed to raise her child in a dalish clan.
I don't have to explain anything. :-) I'm not employed as the writer. I did however show how the possibility exists already within the established story, the reasons for it turning out to be that way would only be fan fiction if I wrote why.
BTW, again, I don't care either way. I just can see it would be possible and easy. And I don't feel it necessary to insist otherwise or slam those who support it. Not saying you slammed someone, just it happens. A lot of negative energy gets spewed here at times.