1. Some posters feel that female NPCs are expected/demanded to be sexier than their male counterparts. And/or
2. Some posters feel that NPCs in general should not be sexy.
Am I right with trying to condense it thus?
1. Yes, but not really in DA series in my case, I think DA is pretty equal in it's treatment of genders, but in my opinion some seems to be against that like OP.
2. Depends on art style, I don't think more sexier style, at least in point of what OP posted next to Cassandra would fit to Bioware's story and art style.
Let's see, I'll continue to answer bolding your texts, hope it's okay so I can focus on certain points:
Then looking at the two reasons...
ad 2: taking this one first, because it's easy. That's a matter of taste in video games in general and definitely not of sexism. You can agree, you can not agree. Fine.
ad 1: There are two possible responses.
1a. Bring down *all* female NPCs to the level of perceived unsexiness as their male counterparts (which is the same response as when you agree with 2).
1b. Elevate *some* male NPCs to the level of perceived sexiness as their female counterparts.
ad 2: Disagree.
ad 1: Both are equally good to me, but doesn't fit to Dragon Age where I think there is balance already, at least in my opinion.
So my question is: Why does the majority of opponents (of the OP) request 1a, when they could just as well request 1b, provided that they are not (possibly also) falling into group 2 (against sexiness in VG in general)? Speaking as a man, I would be perfectly fine with a thread asking for a, dunno, Zhevran-style semi-unclad companion. Why not? In fact, I'm actually strongly in favour of giving women the same level of eye-candy as men, anything else would indeed be unfair; and if there have to be ass-shots at all, then said semi-clad male eye candy should get a share too. So why don't we see more 'give us a prettier male LI' threads from you, ladies? Are you happy with what you got? Is it just not important enough for you to make such a thread?
The thing is that I don't think Dragon Age should be sexied-up, I think that would go against style that Bioware is going with. There is already lot of games that go very sexy, why would Bioware need to go more that way too with DA? 
The fact that these threads all tend to grow to dozens of pages and then end up in the bin seems to indicate that it is important to you, though. But then again, I have to ask: Why not simply start another thread with some input for BW to create guys you can feel more attracted to, if you're currently unhappy? And if you are happy, then why not accept that others (either other women or men) are not and would wish for something different?
I'm rather happy, but this is discussion forum and OP wants to change DAI into something I'd think is horrible and I'll comment about it ^^