I think carrion feed is a good idea, at least, but I would be careful about going too deep into pure sac outlets. The Groff and the Morkrut Behemoth are already doing double duty as good manifest targets and sac outlets (and decent topdecks). Higher creature density makes manifest better in general, though.

I worry that without sufficient card draw or filtering you can end up with some pretty dead hands. Perhaps [[Elven Farsight]] is a safe inclusion that will always be helpful and is great for setting up manifest, too.