Kripp was doing Act 3 with about 530 unbuffed, but around 6400 armour a few days ago (partly owing to high STR, not sure how high. He has some insane 270+ STR shoulders). Not sure how his gear has changed since, though I don't think it matters much, since he did just fine then, too. At least from what I saw.
I can get 200 STR on a chest piece right now for not a whole lot of gold, which should buff me quite a bit, while sacrificing 70 Res All.
I picked this up for like 30k as an offhand.
Cheaaaaap.
IMO, your main priorities are getting enough life on hit so that your regen is really fast, and then have enough HP buffer so that you don't die.
The biggest impact to my survivability was when I got my HP to above 55k. At that level of HP, nothing could really damage me so much at once that I wouldn't be able to heal back.
Your resists and armor seem fine. I'm running around act 3 with less.
My HP is only 30k. Maybe I should focus on buffing that first. Well, second. Step one is getting a main hand that is an Axe/Mace (instead of the sword I bought like an idiot, not knowing that it didn't get the 10% crit chance buff)