I would replace Manectric for Lanturn.
Lanturn @ Leftovers
Trait: Volt Absorb
Nature: Calm
Ev's: 252 Def/40 HP/216 Sp. Def
Moves:
- Scald
- Thunderbolt/Volt Switch
- Ice Beam
- Heal Bell/Thunder Wave
This is more of a tank than a dedicated wall, but with his health + investment in his defences he can fulfil both roles at the same time fairly well. For the last move slot, Heal Bell is for team support, while Thunder Wave might allow him to outspeed some stuff, as well as para-hax support.