After many army lists on Excel (I built my own armybuilder in it) here is the balanced list I have come up with.

1 Sorcerer Lord Lvl 4 360
Dispel Scroll x2
Power stone
Spell Familiar

1 Festus The Leechlord 185

1 Exalted Hero Army Battle Standard 186
Chaos Steed Bard.
Rending Sword

20 Chaos Marauders Mark of Slaanesh 110

12 Chaos Warriors Musician 257
Standard Bearer
Banner of Rage

15 Chaos Warriors Mark of Slaanesh 288
Standard Bearer
Raputous Standard

3 Trolls 135

6 Chaos Knights Mark of Slaanesh 280
Standard Bearer

6 Chaos Knights Mark of Slaanesh 280
Standard Bearer

2x5 Chaos Warhounds 60

2 Chaos Spawn 110

This army is built to either use a strong center or refused flank position strategy. The sorcerers are designed to support the army and I have included several units to slow the enemy units. The strategy is to divide the enemy and conquer it using a classic hammer and anvil technique.

The chaos knights will pressure a flank while the rest of the army moves to engage. This forms my "hammer".

The hounds will move toward shooting units and get butchered while trying to block line of sight.
The spawns will move toward potentially dangerous units. Their goal is to slow them.

Festus and the bsb are designed to work together in the 15 strong warriors unit. This forms my "anvil".
The 12 warriors unit will cover one of the anvil unit flank. The trolls and marauders will cover the other one.
Trolls will be put between the marauder and the 15 warriors unit. The sorcerer lord (the general) will be put inside the marauders unit (I also thought of using flails instead of shield upgrade). I plan to eject the sorcerer if things get hot (maybe sending him in the anvil unit or behind).

Any suggestion or comments on the army or my strategies is really appreciated. Do you see other strategies, unit suggestions/modifications or counter strategies that might work against my army?