I was really surprised reading about Six Feet Under online and learning that not everyone thought Brenda was the fucking worst. Nate too. All the SFU characters are pretty polarizing actually.
I actually included Nate on my personal list, although I don't think I mentioned him here.
He starts out as a decent-seeming guy, very likeable... but then his character arc (where he has typically been "nice" and ends up being the stable one and takes responsibility for everything) involves a huge shift of embracing his shadow side. I think this is necessary for him to empower himself as a maturing adult and become effectual, but Nate never really gets to the end of that period where he can merge his two sides; by the time we leave him at the end of the series, we only ever saw him in that dark, negative, self-absorbed end of things, and he even creates some trauma in other characters. I understand Nate and where he was... but I did not like him much. His negatively disturbed me, and I'm not normally disturbed... it was just so pervasive.
Brenda was a love/hate character for awhile and came to my mind too; I just feel like by series' end, she had pulled out of it and was more likable than not. It's like she does all her crazy and self-centered crazy crap early on, and then slowly climbs out of it and becomes more adjusted. I was left with more positive feelings towards her than towards Nate. I also thought Rachel Griffiths nailed that performance; that was such a hard character to play, to somehow generate a connection while being so unstable and frustrating at times.
Yeah, I have them all on DVD... I loved the series so much, I bought them cheap on eBay or Amazon or wherever I could find them for a low price. Occasionally Best Buy will run in-store sales on them.
And yes, I still have to give the finale my thumbs up as likely the best 15 minute series end I've seen. The Breaking Bad finale is right up there, it's SOOO close... but the last bit with Claire driving off, Nate falling behind in the sideview, and.... I cry every time I see it, and I've seen it at least 20 times!
Hm. I was meaning to do that anyway, since I've been wanting to watch True Detective as well.

Excellent.
True Detective is only 8 episodes. Maybe that will be easier to start with... or maybe you should watch two seasons of SFU and then break it up with Season 1 TD?
(SFU cracks me, I keep thinking "Just Six The Feet Under!" as an expletive when I see the acronym.)
I mean, Lili Taylor even shows up for a season or so -- she's just so great. And Jeremy Sisto, Ed Bagley Jr, Patricia Clarkson, Kathy Bates, James Cromwell, Illeana Douglas, Chris Messina. Even Rainn Wilson shows up for an episode or two, I think.