-Bring back the characters origins like in DAO and maybe add some more like Qunari, Templar, crow, please bring back something similar to human noble also especially if it's in Orlais but no imposed character like Hawke
-Choices from the other games need to have a greater impact than in DA2 where it didn't do much appart from triggering some cameo appearences.
-Gattering an army would also be nice
-More on the Grey Warden since they remind me of the Night's watch and they are sick, maybe learn about what they searched fro in the deeproads (personnally I think that lyrium in which the idol was made is the cause for the darkspawns to search for archdemons because of the "music" like Bartrand and the Matriarch complained about but that's only my theory

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-Bethany and Varric would be nice LI
-How about war between Ferelden and Orlais? Though it might switch the focus from the Templar/mage war so it might not be such a good idea.
-Dwarves, either visit Kal Sharok or discover another city which had been forgotten.
-Combat should be as strategic as DAO but as dynamic as DA2
-I don't think Dragon Age 3 is supposed to be the last of the serie but if it is there are still 2 archdemons so maybe a super-blight with the two at the time... but I hope it is not the last.
-Info on whether Sebastian reconquered Starkhaven or not
-friendship system is good, maybe add a reputation level like in ME3
-Enemies should already be present on the map like in DAO, no backups.
-Dialogues like the ones from DAO, I think it fits the game better than the ME style dialogue option