Toxin is number one priority as BlackcurseLT mentioned, the 10% party damage buff is just too good to give up on.
I usually go for BOTT as second because of the slow aura around you. I don't have 3 sockets so i never use gogok but i think it's pretty useless. A more popular alternative in GR lately is wreath of lightning because of the speed buff, it allows you to pull in mobs faster using the steed charge draw and quarter ability. Vigilante belt used to be bis but lately more nad more people are using Krelm's buff belt, again for the speed buff that allows you to pull mobs. I personally don't really like the buff belt because you can get hit quite a lot and it won't be up for so long. In your case, go for vigilante because you lack cdr in other places.
You don't need to use a gift on your weapon for a zdps crusader so that's one thing BlackcurseLT said that i don't agree with. There's nothing you can gain from a socket on the weapon that would significantly help you on high GR.
In the helm you obviously go for diamond. In general, your gear is lacking cdr. You can probably manage without the cdr on the amulet but that means that you need perfect cdr on everything else.
Also, for GR you want a swiftmount with cdr, str, vit.
I usually use born's chest + shoulders for GR and in trials i use Born's sword + chest and use profane pauldrons for the 6 pickup radius. Also, remember to use shield glare emblazoned shield in trials and divine verdict in GR. Sometimes i totally give up on born's and just use axe of burning sankis in trials. Supposedly it helps with survivability but that's unconfirmed as far as i'm aware.
And remember the proper usage of your pulling abilities. You pull into the pack with steed, you clump everything together with vaccum. When pulling with steed always stay away from walls and corners as those will usually get the pulled mobs stuck. If you are pulling in a short distance and near obstacles, pull out and then back in (away from the pack first, to clear the mobs from the obstacles, and then go inside the pack for a smooth pull). I should probably make a video of this at some point.
Take a look at my zdps crus: http://eu.battle.net/d3/en/profile/Jamoose-2376/hero/39016279
Currently not fully equipped because i swap pieces with the WD sometimes. Notice the perfect rolls of pickup radius on all pieces - This is specifically for running with a 0dog WD in group but it could also work on season with a solanium wd and possibly the hopeful cry law. With the correct gear on, i can get to 20 pickup radius which is really helpful for keeping the dh's hatred up. Btw iirc the only ring that can roll pickup radius is the stolen ring so keep an eye out for those.
Oh and don't forget strongarm bracers. You need a pair with 30% and only toughness stats (str, vit, all res, whatever).