I regret to inform you that unlike Guts, Quick feet does not remove the Attack drop from Burn, so it ruins Megahorn. Replace Flame-orb with Leftovers. Protect does not do a whole lot for you here, I recommend Attract and making it a Female, it is unexpected and makes you more likely to be able to set up the hazards. Most people do not pay attention to the genders of their Pokemon so they will most likely all be Male as that is the default gender. Or get Earthquake for some coverage.
I only see one major problem here, and that is that he can not kill steel type Pokemon. Focus-blast or Hidden-power Ground instead of Veno-shock or Giga-drain would be a good idea.
Have you considered how unlikely it is that you will be able to use Will-o-wisp? Considering there will T-spikes up? Go with Flamethrower for some coverage.
Great set no suggestions.
Venomoth is far too frail to baton-pass without Focus-sash, you will also want to use Sleep-powder instead of Veno-shock or Bug-buzz in order to set up multiple Q-dances.
Ice-beam over Sludge-wave and Flamethrower over Shadow-ball, it will give you amazing 488 Super effective coverage.
Overall a pretty good team. Maybe add Tentacruel with Rapid spin to help make sure your Venomoth gets to make use of the Sash. It would also provide Special tanking. Other than that, watch out for Steel types and other Poison types. Have fun with your team. :D