From the moment fans started playing DAO they have been gushing over the party member dailogues, bantering, and relationships. I would like to see these expanded upon in DAO2.
I would encourage the Bioware team to peruse all the terrific mods that have been developed, especially dealing with char creator options (hair, scars, tattoos, more facial choices, etc), armor, weapons, and screen interfaces (larger text, better maps, viewable console commands, etc), and incorporate these goodies into DAO2. (The modders deserve a LOT of recognition from Bioware, not just the fans, since the toolkit allows them to create some nifty game improvements.)
I realize that my next statement would most likely result in a 2-CD set for DAO2, but I'd pay the extra coin to see some of these implementations. There are a ton of quests in DAO (applause) although there are a ton of buildings and other areas that are non-explorable options. ;-( Some storylines from the Codex can be expanded upon by making them electable quests which would then open additional buildings and areas in which to explore and conquer. Perhaps there could be teleportations into the past (DLC anyone) to flesh out some of these stories.
I hear that the graphics in ME2 are superior to those in ME. I'd like to see that improvement in DAO2 also, but not at the expense of losing party member dialogues, etc.
Bioware did a terrific job on DAO, but there's always room for improvement, hence the dev's interest in what we, the unbridled fans, think and desire. Thank You, Bioware!