I'm not saying it's Not possible. I'm saying developing an open world isn't something Bioware was expert at, and they failed to find a good balance with the story content. What CDPR did isn't easy.
I hope Bioware improves on this aspect in their following games.
I don't think the problem is in that balance per se, but some design decisions.
From my POV, at first, a problem I see it's the feeling that DAI gives to you, it's confusing, in a sense overwhelming.
After a few hours you have 'tons' of missions on the roster without a clear hierarchy (may sound foolish but if you can see the main plot in yellow, in blue the secondary missions and in red the 'filler' ones -fetch quests-, everything would be easier) and on the same wagon goes the war table, no zoom, many banners..., so the interface is lacking some "obvious tips" that would make the life easier. OTOH, as a personal opinion, it's curious that some people is moaning about content that may be skipped.
2nd, the enemy mobs are excessively attached to a given and restricted area (sometimes would be good and logical but always and everywhere...), and the respawn ratio is a bit high therefore some areas seems overpopulated (dogs everywhere!!!).
3rd, the fade breaches should not feel like time sink elements, they should be treated more like a boss fight or so (something not that common), without 'cheapening' them and feeling like 'filler' content (probably less fade breaches had help).
I might add a few more, like the lack of freedom to customize the inquisitor (yep, in underwear, pijama, armor e.g. in Skyhold, etc) anywhere, anytime, but maybe are more a personal matter.
Sorry for going back to DAI but...
About the sidequests and TW3, I don't see really anything to add to DA or ME (as I said maybe more cinematics in the next DA). There are great, regular and bad ones in all of them.