I voted flesh tearers, primarily to satisfy the
CC side you want. By taking them you get access to the
BA codex, meaning Death company / Sanguinary Guard / Dreads/ dozens of assault marines , but at the same time access to Storm Ravens / devastators etc for the shooting.
Can really go either way, though
CC by far the strongest.
As a previous
CSM Player, I learnt fast when facing my regular
BA opponent to kill the Sanguinary Guard reeaaalll fast or ignore them and watch them flank and shred my innocent (
lol) marines.