To be honest, I feel they should include all of the Founding legions. It could work if people would accept the worship of the dark gods as fluff and not something that needs a hard stat boost or some kind of boon.
As a) the Thousand Sons are not there & b) these choices do not appeal too me I choose option E none of them.
About the chapters, I'm going quote the small mexican child from the taco ad "Why don't we have both". I see nothing wrong with having multiple marine characters.
