You can't very well mention Zapdos without also mentioning Thundurus. Not only does Thundurus hit as hard as Zapdos but it can also Priority Taunt Milotic, shutting down all hope of being anything but an attacker. Both Zapdos and Thundurus will OHKO if either carries an Electric Gem; for that reason I'd slash Wacan Berry after Sitrus Berry.
I'd also mention Recover at the very least in other options.
Dragon Tail can shut down Trick Room teams due to its higher priority, as well as just generally annoy your opponent. Against faster opponents Milotic will often go last anyway.
Black FC: 2537-3042-2350
VGC2012 Analysis: Slowbro