Help with my Pokemon Y team?

I want to make a solid team to battle online and I could use some advice!

Lucario (mega), Togekiss (Serene Grace), Arcanine, and either Kingdra or Lapras (for water/ice/dragon coverage)

The last two, I'm debating between using:

Shuckle (Toxic, Swagger, etc)
Espeon (mainly for Magic Bounce ability)

-or-

Cofagrigus (Mummy and defensive wall)
Slaking (unleashed, so to speak lol).

What do you guys suggest? Thanks!

2014-02-26T19:09:31Z

For Slaking, plan is to send out Cofagrius, get Mummy on the enemy, and switch out to Slaking to take Truant out (if they get suspicious and try to switch out, I'd use Pursuit).

?2014-02-26T19:10:03Z

post moves
lapras is not good pokemon for competition due to ice type and low speed
slaking is not good due to traunt
your team is weak to taunt

Edit: id go with espeon and shuckle personally instead