For feature work, or anything narrative for that matter FF still presents one fundamental problem and that's one of focus...the cost of shooting at FF level DOF, is simply not practical and the artistic choice to use shallow DOF to emphasize certain scenes dissapears when everything is razor thin.
Raise the FF ISO by 1 F-stop and close down your aperture by 1 F-stop and now you have the SAME DOF as Super35. Given how clean the FF image is, raising the ISO by 1 F-stop should produce an image that is as clean as Super35.
