Well, we can rule out Honsou right away, because GW can't make characters before BL gives them the say-so, IIRC. Doomrider isn't coming back, because there's too much of a risk of a.) Parents worrying about exposing their children to something like Doomrider, and b.) the very real risk of being sued by Charlie Sheen.
Plus, 19 new kits/blisters and rumours of even more stuff than that? I doubt it. Although I must say I doubt that they'll redo any of the vehicles or add any more non-Daemon Engine/Chaos-only (Usurpers etc.), because that's what the Loyalist Codex is there for. Loyalists should get quality vehicles and wargear, Chaos should get the raw stats and MCs. That's the way it's always worked, in my mind.
But overall, I'll reiterate the fact that this rumoured Codex is FAR too restrictive, and thusly I'm hoping that this is almost entirely wrong.