I've been running 25 NAXX and have cleared it about 4 times (never had Last Laugh drop). I don't have the Sapp quest item, I suck at rolling.
I'm mostly concerned about my block rating. It's sitting at 14.37 after I won the Breastplate of Tormented rage. I was finally able to dump the trinket that provides defense rating and switch to the Essence of Gossamer. I replaced the T7.5 chest.
Should I be looking to switch out gear to get my Block percent up?
Block is sadly best ignored, outside of some specific trash/hc/add tanking set. If you will check the armories of warrior tanks all over the world of warcraft, you will see their block % being close to yours.