Regarding release and bugs.
You can look at games like Skyrim and that is pretty much the worst outcome possible for D:OS, quests that remain broken and are left for the community to fix and players having to find the fixes or workarounds on their own rather than having official fixes.
What I sincerely hope is that they can and have devoted the vast majority of their in-house QA to the pieces of content we have yet to lay eyes on and let us find the remainder of the bugs in the content we have access to and simply fix them as they come aware... as well as of course having support going forward after release. The gist of it, use the alpha and beta for what it was intended for, which is very much what they have been doing, and focus internally on things that they can't or don't want to make use of the beta for.
I am not worried about bugs on release, because it is just something that will be a factor, how big of a factor we do not know. Hopefully not a major one. But I can guarantee that D:OS will have a list of known issues (internally) going into ship that they just couldn't fix without pushing their internal deadlines even further and making the game into an eternally unfinished game. How major or noticeable those issues are and what they can do about them after ship is what really sets the course for this game going forward.
The quality of the initial release is more of a testament to the quality of development/content before they went into the bug fixing phase on it to begin with, because no-one creates bugs intentionally, and their ability to prioritize in what order to tackle issues discovered after a piece of content is initially deemed complete and/or "release quality".
