9 games are not enough to judge EJ. Injuries, inconsistant offensive line play and an uncreative offensive coordinator dont help.
If the Bills fill their needs of G, LB, and if Byrd leaves, S, then yes a 4th rounder. Marrone has been preaching competition since he got here. EJ would still be the starter year 2 but if he faulters year 3, at least they would have a QB who knows the system.