If you can link to your character, I can see what kind of gear you've got on.
There are three items that I use that help significantly with keeping aggro away. One is the
the second is Maximus: http://us.battle.net/d3/en/item/maximus
third is the Waling Host + Litany of the Undaunted set: http://us.battle.net/d3/en/item/the-wailing-hosthttp://us.battle.net/d3/en/item/litany-of-the-undaunted
The Gidbinn is not very powerful but will summon mini-fetishes that can draw about two hits before they die. These spawn at about the same rate as your sycophants, only you have a maximum of three out at a time. Being a one-hander also allows for a mojo.
The Maximus is ilevel 63 as opposed to the Gidbinn's 61, and so you can get some great stats on this one if you have the money to pay for it. It summons a very large demon (with fire chains) that is actually much bigger than your Gargantuan. I don't believe he does as much damage, but whenever I pull him out (he spawns fairly often and sticks around for a while) he blocks doorways and hallways easily, forcing mobs into either attacking him or my other pets.
The Wailing Host/Litany of the Undaunted ring set may sacrifice a bit of your dps or your tankiness, but it gives you yet another passive summon - you get the chance on attack to summon up to three skeletons (either swordsman or archer). These also have low health and will probably die within three shots on the MP you're running, but in dire need these guys have saved me more than I can count.
And finally, an item so weak I don't even use it, the Grin Reaper: http://us.battle.net/d3/en/item/the-grin-reaper
It's stats are really pathetic at ilevel 58, but if you're willing to sacrifice power for more distractions, this one might be worth it. It summons 3 "Mirror Images" of yourself that utilize your attacks and distract enemies. While they don't do any damage, they are fairly constant and help out quite a bit.