Voodoos, without buffs, don't have enough HP to worth gravity pulling in my opinion. Could keep a few as a safeguard, but I'd rather focus on more damage.
At first glance, I'd try it out with 4 upped gargoyles and a Vampire Dagger in place of 2 dragons and 3 voodoos. This would have the effect of faster creature deployment and more overall damage in the deck, plus a bit of healing through the dagger. Dusk shroud and Eclipse would be also very helpful, and could easily turn games around for you.