There possibly will be, since we do have the option to chose a fifth legion for chaos, and Thousand sons are quite popular...
While i admire your hope seeing as they have given 4 undivided warbands and talked about how they want to expand on the gods post launch i doubt we well see any of the 4 god legions. Then again i hope im wrong to the bone.
I did.That doesent mean we choose what the options on the poll they themselves make are. They make the election, we choose from the candidates. But again i hope they surprise us.
I think out of the expansions to the main content we will definitely see Chaos God specific themed PC archetypes and NPCs, I wouldn't worry about it really it seems like a no brainer. I'd worry more about how alternate factions that exist within a certain side will play a role and be implemented like IG or the SoB.
Er... dude, are you honestly posting that everywhere? Because you do know that's technically spam... in a way...