Yes, I agree that if the Dalish should lose faith in their gods that is no reason why they should automatically convert to the Chantry. However, until such time as they are released, nothing has really changed. The ancient trickster Fen'Harel rubbished the memory of their gods. Well he was the one who imprisoned them so of course he'd be trying to justify himself. Particularly since the Dalish teach they trusted him and he betrayed them. They know their gods are shut away and can't answer them. The revelation about Mythal might give them pause since Lavellan actually met her and so she was able to confirm her murder if nothing else. However, they have based their culture on following a model for living that they believe was given to them by their gods. For all they know it might have been. In any case, it has served them well enough since the fall of the Dales and ensured their continued survival. So there is nothing wrong headed or stupid in having continued "faith" in that.
Yeah, the Dalish are still a nomadic group so there wouldn't really be much of a drastic shift in how they live their lives - they may revise their vallaslin to represent something other than the Evanuris, for example, but they would still hunt, work, look after each other, protect the clan from the dangers of the wilderness and any humans who threaten them, so the basics would remain the same. I don't see them capitulating to conversion to the Chantry or human rule after the centuries they've suffered simply to maintain their autonomy.
Also modern Thedas came very close to extinction during the 1st Blight. It was only through the initiative of the first Grey Wardens that civilisation was saved, and some of the knowledge to defeat the Blight did in fact come from elven slaves. So all those old memories handed down turned out to be useful for something.
True, the elves were said to be instrumental in helping create the Joining ritual.



