Well maybe we could Get The Red Corsairs and the Crimson Slaughter to work together somehow, especially since the Crimson Slaughter are Enemies of the dark angels and the Red Corsairs like to pillage and steal. In fact since most of the new chaos marines are only warbands and I'm only Guessing that Legions are bigger than warbands (Sorry if I'm wrong), then could it be possible for all the new Chaotic warbands to form a new "Unified" legion of their own? This is just an idea, so please don't be mad if i made a mistake about this, but to me it still would be cool if something like that happened though.

Dont get me wrong, i too would really like if they brought in some lesser known warbands and gave them the spotlight. It's just the Crimson Slaughter doesnt appeal to me. The Blood Gorgons do and theyre probably just as well known as the Crimson Slaughter: The blood gorgons got a novel while the crimson slaughter were included in that TT pack with dark angels.
Also i think the Blood Ravens didnt even exist before DOW because they were created specifically for it. I really hope theyre in EC though, not only are they mysterious and interesting but theyre the face of 40k in video games currently.

Yeah i guess it would make since to add Blood ravens in, but that might be a problem due to the Blood Ravens losing half their Chapter to Chaos in the DOW 2 Series.

Red Corsairs would be a great addition but I can only see it happening after the core 'legions' are integrated into the game as they are the most well known.

this was my first thought--its a perfect excuse for allowing a shitton of different chapters/color schemes in one warband/faction

i thought the red corsairs still make new renegades wear their colors.

They don't, the only thing you have to do is deface the Imperial eagle. I wouldn't mind seeing the Red Corsairs but they will not be added until all the other main legions have.

I'd want Red Corsairs, only to be a Night Lord and re-enact a scene in Aaron Dembski-Bowden's Blood Reaver novel where the Night Lords are hiding behind a group of Meat Shields Red Corsair Terminators laughing their asses off telling them "Your doing great!" As they are being shot by a massive barrage of Bolter fire XD

i agree with JC his logic is undeniable

Wait...what? Night Lords...messing with people? Dare you say. /sarcasm.

If they are up for that I say let them in!

Kidding, I don't dislike the Red Corsairs, I just think it will be one of the more popular and long standing undivided Legions that ends up being in at the start. Hopefully we handle it better than the SM's did when they were told the BT's would not be on the list to be voted for as the 5th chapter. There was like a no kidding near melt down over there.