I'm in the pro-Viv camp. I don't really see why she gets this much hate, while Solas doesn't (who has kind of the same attitude, just in a different direction). I expected it to be the other way around. The way Solas insulted my Qunari was the biggest Renegade moment I had in a DA game. Viv can be a condescending ass (though I don't actually think she's done it that much, most of the time it was just being honest), but she wasn't racist. Her banter with Bull showed that she actually respected him a fair deal (a thing that some people here apparently find her incapable of), her attempts at making him more fashionable wasn't really insulting, Bull was willing to heed her advice. To comment on Blackwall's lack of hygiene was perfectly justified as well. No one likes having a smelly peasant around in close proximity. She does bring elitism a bit higher than she should, but that's her main character flaw. You know, stuff that makes characters actually interesting.
The way the conversations with her were constructed (Viv always getting the last word and being generally unimpressionable and stubborn) is part of her character. There are people who just make themselves very difficult to argue with, and are just better be left alone. I don't see the assumed poor writing here. So what if you can't kick her out? She'll be perfectly fine alone on her fabulous balcony.
Her rearranging of the furniture with no option to oppose her was a bit iffy, I can agree on that, it's no biggie though. She does have good taste.
Even if I wasn't pro-templar in general and wouldn't find most of her points sensible (she does acknowledge that the Fereldan and Kirkwall circles were terribly restricting, it stands to reason that she would see them changed), I'd still find her a great character who maybe needed a bit more fleshing-out. The less impressionable yesmen I'm surrounded with, the better.
Templar brutality this, Mage irresponsibility that, my lil' sweetheart Minaeve's life story and a glimpse of Tevinter history (as well as the effin Blights) makes Viv's way the most reasonable for me. Not perfect, the Circle system would definitely need a few reforms, but it's the most sustainable on the long run. Making Cassandra the Divine who'd be willing to cooperate with the mages and the templars to create a more balanced system is my best case scenario.
Not putting Viv on the Sunburst Throne though, that would be too soon. One step at a time.
I think she's in a similar position as Morrigan was (I was also surprised back then by how many people disliked her), but didn't get as much attention in the story or in her dialogues. Both Morri and Viv have deep insecurities under the cold fish facade, but with Morri we got a chance to address these and actually help her or at least understand her better, with Viv we didn't. I wanted to know more about her backstory, feelings, fond memories and most of all, addressing her fears and issues. It could have helped building up more sympathy towards her the same way it did to Morrigan.
Actually, I think this is why we didn't have any characters in DAI who could measure up to the Alistair-Leliana-Morrigan trio, or the Cassandra-Varric duo to the point when they would be worth bringing back in future installments. As much as I liked some of the current companions, none of them feel strong enough to be revisited again, especially in a different setting, while on the other hand the aforementioned ones could easily justify yet another comeback.
This is all just an opinion of course.