What do you think about this competitive team?

Cofagrigus (Female) @ Sitrus Berry
Toxic
Hex
Shadow Ball
Energy Ball

Registeel @ Steel Gem
Flash Cannon
Earthquake
Superpower
Thunder

Milotic (Male) @ Mystic Water
Hydro Pump
Surf
Ice Beam
Recover

Does this team have a lot of flaws?
P.S. Milotic is in almost ALL of my teams so I'm not gonna replace him for this team, ever.