Here is my list so far

Herald of tzeentch
- Master of Sorcery
- Spell breaker

Bloodcrushers x 2

Flesh hounds x 5

Bloodletter x 20
- Banner
- Champion

all advice would help.

I personally would take flamers over bloodcrushers, they are too good to pass up at this point cost, and they won't go down easy in combat... thats the only difference i would make... it also gives your herald of tzeentch a bunker of sorts

I agree with zhambah that if you want to optimize the list you'd probably replace the Crushers with Flamers, but at this level Crushers probably wouldn't do too badly for themselves (unless you run up against Cannons, Bolt Throwers, or Doom Divers). So either should be fine.

I would definitely recommend replacing the champ in the Bloodletter unit with a musician though. Free reforms are awesome! Also, Spellbreaker is only going to be necessary if you expect to face lots of magic. A lot of the games I've had at these levels my opponent doesn't even bring a caster. Winged Horror could help the Tzerald to bounce around and get line of sight/range for its spells, as well as play peek-a-boo with wizard hunters like Eagles.

Finally, you'll have to pick which lore you want to take on the Tzerald as well. I think that Light is probably your best bet (especially if you take Flamers), with Death probably also looking pretty good. I might also consider Life or Fire.

I have been using beasts for the lore of mastery.