I'm kind of glad that they handwaved the OGB in DA:I. I'm also very glad that they had Morrigan mellow out and become more human. It wouldn't have been realistic if my Warden had no affect on her personality.
Problem is that Morrigan acts the same way in Inquisition regardless of how your Warden dealt with her in Origins.
-at the end of Inquisition they never gave any real solid rationale for Morrigan wanting the OGB in the first place beyond their insistence on giving Morrigan really vague notions of wanting to preserve ancient knowledge for no reason besides preserving it.
Her mellowing is independent from her experience with the warden,tough honestly i can't imagine how she can afford to act in the same way of DAO with an empress and in a pool of Orlesian sharks.
The well of sorrow quest is just another example, it does not matter her past experience and/or the existence of Kieran her behaviour is the same.
-that's why i strongly believe that she hadn't any plan ,she just try to do what she was taught to do that's why she wanted the OGB.
Preserve because FLemeth taught to her and the Inquisitor can ask to her why she want to preserve things,she just answer it is because she must.