Since Reuniclus won't ever try to outspeed anything, and you probably would have other Trick users, I recommend
Reuniclus @
Life Orb
Ability: Magic Guard
Nature:
Quiet
EVs: 252 HP / 252 SpA / 4
Def
Psyshock /
Psychic (both can be an option, former if you don't feel like Chansey/Blissey walling you ).
Focus Blast
Shadow Ball
Trick
Room
Eelektross @
Lum Berry
Ability:
[COLOR=blue ! important][COLOR=blue ! important]Levitate[/COLOR][/COLOR]
Nature: Quiet
EVs: 6 HP / 252 Atk / 252 SpA
Thunderbolt
Flamethrower /
Hidden Power Ice (HP Ice has will hit Grass, Flying and Ground for super effective damage where as Flamethrower will hit Bug, Steel, and Grass).
Brick Break
U-Turn / Volt Switch (You can opt for Volt Switch since no one in the right mind will try to counter Eelektross with a Ground-type Pokemon unless, of course, Gravity is applied).
I agree with PlatinumDude to replace Starmie, you don't have anything weak to entry hazards anyway.
And isn't Gastrodon annoying enough? ._.