First off, chardev.org kicks butt, most up to date site of its kind that I can find. With either of the options below I would eventually replace the gloves with Handguards of Revitalization and the legs with Endless Void, unless the 4 piece is better than it seems to me. Also Sorthalis isn't on the site yet.
Either one easily puts me at block cap (raid buffed). I mt about half the bosses, so that is the reason for focus on avoidance and not as much on block. With the 4 piece, could regem for more stam, but I haven't seen much of a reason for more than 34k unbuffed so far in uld.
so yeah, spent way too much time on this so far, can't freakin decide:
http://www.chardev.org/?template=169952
4 piece bonus (minus gloves)
http://www.chardev.org/?template=169969
2 piece (helm and chest)
4 piece:
Gemmed for socket bonuses (stam)
lose: 900 armor, 220 health, 1.3% hit, .5% dodge
gain: 4 defense, 1% parry, 2.4% block, 89 block value, get to wear a dress while tanking