Pokemon X Competitive Team?

So I've been trying to make a competitive team for this game but I keep getting torn between which pokemon would be good.

My team is

Greninja

Gardevoir

Metagross

Blaziken

Goodra

The last pokemon is so hard to choose. I've had like aegislash, gengar, scizor, noivern, charizard, and lucario. I was thinking about using Jolteon but I don't know... Please help. Thanks!