Okay, breath guys. Breath.
First, I don't believe people are asking for a setting below the already established Casual. What they're asking for is for the casual setting to BE a Narative type setting, where combat is a mostly non-issue. And honestly it really is already. At least for DA2.
And there's nothing wrong with that. Because not everyone has the physical ability, the time, or the drive to want to play in the more challanging modes. Having this less-then-normal mode, something that's already been established in several of Bioware's games, detracts from nothing. They aren't going to suddenly stop creating nightmare mode because they now have a mode with the AI and health of monsters turned down.
It also isn't a resorce hog some folks might claim it to be. Tuning down the AI and the health % is by far LESS difficult then tuning them UP. Because tuning them UP in the more difficult modes requires extra work to make sure player spells, abilities, and weapons ballance out to meet the challange. Tuning the difficulty down to Casual or Narative does not require them to retool gear, spells, or area effects. It just takes tuning down the AI and health pools of monsters. Leaving abilties and spells at normal levels and tuning down monster AI -- or even leaving monster AI and healthpools the same and throwing a 5% modifyer on all abilities.
And let's not forget what we already know about how the game will work.
From what we've been told up until this point, most combat encounters that happen outside the main story are almost all optional. Sure some may effect what happens DURRING the story (Aka: Leaving the high dragon in the zone where your keep and towns may be might be a bad thing) but the random roving pack of wolves probably aren't going to cause to much of an issue if you chose not to engage them. Of course not engaging them may reduce your amount of mats for armorcrafting... but that's on the player, and not really a detraction of the story what so ever.
So from what we already know, gameplay is already different then it has been up till this point. There will be "scripted" combat that is story-linked, and "non-scripted" combat that is optional. So at the very best all some folks are asking is IF there are difficulty sliders/settings, that the non-optional "Scrpited" story combat have a level that you can choose to make it be less difficult so that it doesn't feel like a slog to them. That it doesn't detract from the story. Any optional combat outside of the story is optional and if they chose not to do it, that's something that they themselves have to deal with (via the concequences of leaving a high dragon to roam or not having those shiny nug pelts for their boots)
All in all, I have no issues with folks who can't or don't play in the higher difficulties. When I play the higher difficulties, I feel challanged. And I enjoy that. But I'm not other people, and I have no right to force them to play a single player game the same way I would. If they add a Casual/Narative combat level, I'm not hurt by it. It just enables folks -- like my disabled brother -- to enjoy the world I've fallen in love with. And being able to share the overall experience with him and others like him is a good thing, not a bad one.