Poor storytelling is somewhat neither here nor there because everyone has different opinions on what is good and what is not, they very well could do something completely stupid and think it's a good story. (ME3?)
I think a lot of the symbolism is accidental (reuse of statues or whatever) but some of it has to be there for reasons we can't see yet. 
Yes, there may be objective criteria for poor storytelling like obvious contradictions or shallow stereotypical characters, but mostly it's very very subjective.
Often we project more clever things onto something than the person who created it. But so what? What matters is what people get out of something. And if they enjoy theorizing and come up with great ideas others even appreciate contemplating, that's wonderful!
Personally, I consider anything that allows for such extensive theorizing a success. In the end the actual intent doesn't even matter. If we like what we see we shouldn't let others ruin it. That was my issue with BSN after ME3. I loved the game so much and had no problem with the ending. I thought the execution was poor but I thought it all made perfect sense. I firmly believe in the indoctrination theory and the shitload of evidence in the game that supports it - that doesn't mean others have to interpret the games the same way. But the amount if ridicule and resentment upset fans had for those who were happy with their interpretation made me leave BSN.
I feel the same frustration with the hate for DAI. The game is as good as we want it to be. Bioware games allow for intensive theorizing and that is something I love them for.
I feel that many people don't give Bioware enough credit for their subtext/mythology. They do have a plan and an endgame. They always drop many hints and DAI is the best proof how everything is connected. And that there is MUCH more going on than mages and templars. That is fact, the game states it. However, how complicated this all is comes down to personal interpretation. Bioware will most likely keep it open. I like it when something is not spelled out, so that everyone can draw their own conclusions. But when there are enough hints that do make sense if we manage to piece them together. There usually is a message/a meaning. It just might not be quite as philosophical or brilliant as we thought. Some things are just coincidence but our adaptive minds can find meaning in everything. Theories are reflections of the mind of the theorizer not so much the art. And it's all good that way. Stories are meant to be fun and maybe make us think.
Bioware gives me what I seek, so I'm happy.