I prefer the massive increase in mainstat over the PvP armorings. After a lot of experimentation I have found that it simply works better for me, regardless of my enemies' expertise ratings. It is personal preference, but I can with absolute certainty that I always do best when it is so "low."
I wouldn't go much lower than 1150 though, for dps assassin anyways.
ALSO I UPDATED MY ARMORY SO CHECK IT OUT
also I posted a thread in 4 subforums yesterday (this one, shadow subforum, PvP subforum, and The Bastion's subforum) about why DPS assassins can be good in rateds. Has some important points that relate to the class as a whole and how you should play it in PvP so I strongly suggest reading it. I will add its 2300-word content to this guide once the actual threads die out.
I read your 4 pillars of assassin dps post, how I was lead here so I read your post. Pretty good read and very informative. Ty for posting it as I didn't feel like searching for these guides and i'm always downt o learn more about playing classes I like.
Don't you feel you're a little too squishy though without the insulation talent and so low of expertise? You're in like medium armor with the procs up blackout is a good defensive cd but I feel the whole 24 seconds of up time only really shines in a 1v1 situation and you have to blow quite a few cool downs for it.