I'd love to see a Val Royeaux of this description. I feel like they have that ability in the next DA also depending on the plot or the circumstances. Maybe if say the Qunari, or Tevinter officially came marching down on Orlais and Fereldon. Or something of that nature.. I think it'd be a fantastic sight to see said Val Royeaux.
Since we're going north next game, it is doubtful. That said, there could be a DLC involving Val Royeaux that shows it off.
I would love that, won't make up for it not being in the base game, but it would be nice to see.
Since we are going north that leaves several main countries to explore, Rivain, Tevinter, Anderfels or Antivia. I want the next game to be either Tevinter or Rivain myself.
If we go to Tevinter, I want to see the main capital of Minrathous in all its glory. I want to see the circle of magi here, I want to see the slave markets(and MAYBE do something about them) I want to see normal tevinters going about their normal day. I want to see the dwarven proving grounds and embessay. I want to see the massive golems called Juggernaughts. I want to see the argant spire where the black divine lives. I want to see the city in its glory and horror.
If we do Rivain though, we have several places with different designs to use since the country is rather divided. You have the capital of Darismund which technically rules the realm, it follows the southern chantry. You have the fortress town of Kont-aar, a peaceful Qunari fortress on the mainland. Then you have the free city of Llomerryn, which is filled with pirates and other sort of people of all types; though it was the place that ended the exalted marches. Have several villages and towns throughout the region, this would give each major area its own feel and look. 
One aspect that the Witcher covers really well and I was left wanting in DA:I is the horror aspects of certain enemies.
I'll take two examples, in The Witcher 3 there are 3 "Crones" (witches would be a better description) that exert immense power over Velen. To say they are unpleasant would be an understatement, I felt like I needed a shower after talking to them and the entire swamp should be left int he capable hands of Aerys of the House Targaryen second of his name or the High Prophets of the Covenant Regret, Truth, and Mercy.
Seriously those 'women' (using the term extremely loosely) singlehandedly make the case for oppression of mages in TW3 universe.
Whereas in Dragon Age there is some sever lack of seeing the horror aspect of many vile creatures and people. Red Templars are the best example I can think of given the lack of abominations, though I suppose the Envy/Nightmare demons might work. We hear about how horrible lyrium transformation is, and we run across people who have been through it, but it still lacks emphasis and punch. There is no visceral reaction really and what should by all accounts be atrocious creatures, are fairly "clean" looking.
I won't even touch the botchling though
Agreed, monsters here are monsters. I want to see the horror and dread that monsters inspire, the crones especially are good examples.
I liked the Botchling it was adorable 