Funny, I always considered my first, unspoiled playthrough with all its warts to be my canon. So, I wind up with rogues.
My Warden was a hapless Noble Rogue who was going to rule Ferelden with Alistair ... but she couldn't stomach the idea of the Dark Bargain. Sooo, she was going to do the US, but she took Alistair up the tower with her. And the big goof took the final blow himself. So with Anora back on the throne, Aislinn felt it would be politic to wander the world for a while and disappeared.
My Hawke romanced Anders. Oops! Big Mistake! How embarrassing when he goes off the rails and blows up the Chantry. She didn't see much choice but to murder knife him and her heart all at once. Even though she didn't have to kill anyone despite siding with the mages, she also wound up wandering off alone.
I imagined the Warden and Hawke sitting off alone in some dingy little dive bar drowning their troubles. So saying that they disappeared in the proper canon of my game is accurate although their reasons for disappearing in my head my differ somewhat with what the devs have in mind.