The history of Thedas stretches back centuries, with the past often misunderstood by the contemporaries who embrace it. For example, it's very clear that the Dalish do not completely understand the ways of their ancient people, as highlighted by Solas in Dragon Age: Inquisition. One thing that could be misunderstood, or at least lacking very important context, is the Blight, but it's possible Dragon Age: Dreadwolf clears some of this up. As fans know, a Blight occurs when the Darkspawn find and corrupt an Old God, with these beings existing somewhere underground (or, at least, so far in that it's implied). The Old God becomes an Archdemon and leads the Darkspawn in a war on the surface.
The archdemons can only be killed by a Grey Warden, as the Old God's soul travels into their mortal body, dies, and the rest of the Darkspawn have no direction anymore. They retreat underground. Dragon Age: Origins' Fifth Blight goes a little differently though. Not could it end by saving the Old God's soul, but it begins by The Architect intentionally seeking out the Old God and attempting to convert it to a Disciple by giving it Grey Warden blood. It wasn't malicious, as the Architect sought peace for the Darkspawn, and this reason is why a Darkspawn companion could and should appear in Dragon Age: Dreadwolf.
How Solas' Plot in Dragon Age: Dreadwolf Could Put Darkspawn on the Same Side as Humanity
The Darkspawn, for better or worse, find themselves at the crossroads of several distinct lore bits. They are the reason Dwarven civilization has collapsed, and many blame Tevinter for creating the Blight, giving the country an even worse reputation (though deserved). Corypheus seems to confirm that entering the Fade is what created the Darkspawn, and he was a Tevinter Magister seeking the Call of the Old Gods there. This ties them to the chantry, while the Old Gods were worshipped in Tevinter. Grey Wardens and the Blight have left a huge impact on Thedas, resulting in the stories of DA: Origins, DA: Awakening, and to some degree, Dragon Age 2.
Perhaps most importantly though, they may be tied to the Elves. There are many theories that the Old Gods are some physical remains of the Evanuris, who were domineering Elven "Gods" that Solas rebelled against and locked in the Fade with the Veil. After all, Solas speaks with disdain about what the Grey Wardens do with the Old Gods.
On the assumption this theory is somewhat true, it shows how the Darkspawn are potentially another dangerous effect of Solas creating the Veil and how they are Darkspawn who, once freed from the song, are capable of critical thinking. Part of this is because Darkspawn are created from Broodmothers, but it's clear that Genlocks are corrupted Dwarves, Hurlocks corrupted humans, Shrieks corrupted elves, and Ogres corrupted Qunari. Whatever Solas is doing will no doubt impact the Darkspawn, potentially even create a Blight or set off future Blights, but if any of The Architect's disciples remain or somehow have broken from the song, it may be peace for their people is what they seek too.
Because of these inherent connections, it would be interesting to see the Darkspawn follow in The Architect's footsteps and try to stop Solas' plot, as it could negatively impact them too or drive them mad if the Evanuris/Old Gods are set loose on Thedas. A peace-seeking Darkspawn opens up a ton of doors for Dragon Age: Dreadwolf's story, and while these could just be big, important NPCs, having one as a companion would be the best way for the story. After all, the Warden Commander (if alive in Inquisition) is searching for a cure to the Calling, and it's possible what's used to cure the Grey Wardens could also "cure" the Darkspawn. This would be a big development and would fit right in with everything else going on.
One could argue how Darkspawn corrupt humanoid beings around them that are not Grey Wardens, but this factor could be swept under the rug as it was with the Darkspawn blood-soaked companions of Dragon Age: Origins. Or perhaps "cured" Darkspawn no long have this ability. Either way, having a Darkspawn in the party would not only make a more interesting story, but it would make for a more complex one too. That's not always a good thing, but here, it definitely would be to see the eyes of Thedas through one more culture.
Dragon Age: Dreadwolf is in development.