David Gaider - a well-known developer and former employee of the Canadian studio BioWare, who worked, among others, on the Dragon Age series - told us how the improved version of the second installment of the series could have looked like.
1
IN A NUTSHELL:
Former BioWare developer and Dragon Age co-creator David Gaider shared on Twitter his vision for a revised version of Dragon Age 2, a title that was considered unfinished by many players. While no such project is planned, but if the developer had the opportunity to improve his work, a few things would certainly change, beginning with the city of Kirkwall itself.

In a situation where the player character is a mage, we would also get a new plot thread that would show how Hawke almost becomes an abomination (in the DA universe, these are creatures are created when a mage becomes permanently possessed by a demon - the risk of this happening is always there when someone uses magic). Gader thinks that the fact that Hawke is the only mage who doesn't seem to have to fear such a fate is quite a narrative problem.
The creator would also like to restore a whole bunch of cut dialogue lines and fix existing ones that didn't make sense or created plot holes.

There would be a lot of changes in the third act of the game - it would be expanded to make the finale not seem so sudden. There would also be alternative endings to battles and storylines of several characters.

Gaider would also want the hypothetical revised Dragon Age 2 to feature a romance thread tied to Varrick (there would also be more moments in which Varrick adds some flair to the story before being set straight by Cassandra). The list of changes would also include a more expansive prologue that would allow the player to get to know the Hawke siblings better.
Former BioWare developer also mentions an expansion for Dragon Age 2 that was planned but never developed - it was to be titled Dragon Age: Exalted March and would have ended with Varrick's death (which would have also meant some big changes for the story of Dragon Age: Inquisition).

Looking at the extensive list of possible changes and fixes, it's a bit of a shame that a revised version of Dragon Age 2 will never see the light of day - even the original release, heavily criticized by many right after release - actually has a lot of merit and tells a decent story. If only the developers had been given more time...
1