I realized that my team is suddenly without a fire move, rendering me helpless against opposing Skarmory, Ferrothorn, Forretress, Scizor etc. and Tyranitar's Fire Blast is shaky at best.
85% accuracy is still acceptable.
If you want a Fire move, a Mega Venusaur check/counter and a revenge killer all in one, use Talonflame:
-Swords Dance
-Flare Blitz
-Brave Bird
-Roost
Nature: Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Life Orb/Sharp Beak/Sky Plate
Ability: Gale Wings
or
-Flare Blitz
-Brave Bird
-U-turn
-Tailwind/Roost
Nature: Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Choice Band/Sharp Beak/Sky Plate
Ability: Gale Wings
or
-Bulk Up
-Brave Bird
-Roost
-Taunt/Will-o-Wisp
Nature: Careful
EVs: 248 HP/8 Def/252 SDef
Item: Leftovers
Ability: Gale Wings
Of course, you still have to use this with Starmie, since Talonflame is 4x weak to Stealth Rock.
Anyway, here's what the team should look like, IMO:
Talonflame/Starmie/Aggron/Tyranitar or Gyarados/Scizor/Dragonite
But the team is still chock-full of physical attackers, so dropping a physical team member for a special or mixed one may be a better idea.