I have been pondering about Daemon lists since the codex come out. I think I am going to go heavy big monsters along with Flesh Hounds. I've only play tested the big monsters and Flesh Hounds once and they did very well. What I have my doubts on is the troops.
Pink Horrors, yo
As I am a shooty player I have been looking at Pink Horrors for troops. They can put out a decent amount of fire power if there's another of them (4D6 shots if numbering 16 or more) and if you add in a Herald with locus of conjuration you can make those shots S6 and also re-roll to hit (Herald takes prescience power from divination), pretty damn good. Also thanks to the brotherhood of sorcerers rule, you only need one Horror to get LOS, the rest can hide away easily.
Unfortunately it is not all rosey, the Pink Horrors only fire 4D6 shots if they have a large number, the more they get depleted the less shots they fire. They are also psykers, fail a psychic test and no shooting for them and lets not forget about deny the witch as well - that's two chances there which can stop Pink Horrors from shooting. Normal