Well, your army looks great, I personally wouldn't use Chaos Bikers at 1000pt unless they are given a Power-Fist or Meltaguns, Bikers are great units its just that they need a specific role and should be equipped to suit that roll. Another problem about your Bike Sorcerer and Bikers is splitting your army is a bad idea, those 4 guys would be torn to shreds against enemy fire and/or getting stuck in close-combat with infantry.
I would suggest dropping the bike on the sorcerer, possibly the whole biker squad (its really up to you) and add a Daemon Prince or Lucius the Eternal (Lucius is great because he has awesome melee and is armed with Doom Sirens.)
You can look also look the 2000pt Slaanesh army list my friend wrote and see if it gives you any inspiration
http://www.dakkadakka.com/dakkaforum/posts/list/347949.page