Oh yes, I know. I was never such...uh, equipped. I have quite a few friends that were packing, though, in spite of the fact they were tiny built. Women do literally come in every shape and size-- and none of them offensive.
I wasn't telling so much you, as I was the person that's insisting that big boobs were "disrespectful." That's wonderfully ignoring that in many cultures, large breasts are a symbol of motherhood. Andraste is seen as a mother by most of the human population of Thedas, so it makes sense to me. Not to mention that I don't spend the game staring at my staff. I'm usually more concerned about my footing, or I'm gathering something. Yeah, I know I can buy/skip a lot of that stuff, but it's the best way to find rare herbs and Fade-touched ore. 
Secondly, I have the screenshot where Cullen is talking about the time a templar lost all of his clothes. According to Cullen, the man "Stood up, saluted, turned on his heel and walked out like he was in full armor. The entire room started applauding." So there's that.
Also, the Cassandra quote made me giggle, because she's one of the most buttoned-up characters in the series. Naturally she's going to be uncomfortable with nudity, and she certainly does not reflect the attitudes of Thedas as a whole. I mean, does most of Thedas get turned Tranquil and then commune with a Spirit of Faith? I'm not saying that the Spirit aspect changes her any, but I do wonder if being turned Tranquil during the Vigil might have something to do with how tightly she keeps everything in. Plus, years of training and learning to be more of a fighter and interrogator puts her in a unique mindset.
She's a lot like Aveline, in the sense I can see both lady warriors not being comfortable with nudity.
Cass has learned for years (since DotS, so 18-20ish years by now, if not going back to her noble/royal upbringing) to keep herself at a distance from everyone. Her only romantic outlet (unless she romances a Lord Inquisitor) is her romance novels. Otherwise, even she'll admit that at times she stays too focused on the task at hand to really get to know the people around her.
He keeps bringing up the Black Emporium Andraste codex yet again, which is rather humorous. It ended up in the Black Emporium, along with the Barrel of Lost Socks and the twitter reference. It also is a reminder that even the writers have said that not every codex should be taken as the literal truth. Considering all the other out-of-place references that are in there, I don't think we should take most of what we read from TBE as lore.
I would also figure that, if you brought Sebastian during the Legacy DLC, he'd comment on it then. That's where the tier 3 piece originates from after all. He doesn't, nor does anyone else. I would rank Sebastian up there with Leliana in terms of overall pure faith in Andraste, so he would've spoken up.
One of the few things I liked about Sebastian was his faith, but he did talk about it an awful lot. That would have been the perfect time to mention it. Or even Anders. Remember, he did comment on a statue of Andraste during Awakening, as well as Sebastian's...belt buckle in DA2.
Edit: Malcom's Honor was originally crafted so Malcom Hawke's staff wouldn't draw attention while in Lothering. Apparently, it worked well enough to were the family was able to hide just fine until the Blight. If the breasts being too large had been a problem in a tiny village in southern Ferelden (where folks call that country "backwater") I think the rest of Thedas is okay with it.
Look, at this point, anyone is free to politely ask David Gaider about this. I stress politely, but there is actually a good chance he might answer. If folks are polite and don't spam him, he's pretty good about answering lore questions so long as it doesn't directly spoil the next game. Twitter seems to be the best way of reaching him. Try to find a way to word it in short characters, but simply ask him if the people if Thedas care if Andraste has big boobs on the staff piece. I bet the answer will be no, mixed with some serious snark.