the bears dont have the interior o-line presence that the saints have. in new orleans , bushrod succeeded because they were able to slide the interior line or scheme in chips when needed, on top of drew's ability to seamlessly slide inside the pocket.
hes going to be expected (or at least i think they are hoping he will be able) to sit on an island in chicago and handle his man 1on1.
i think with time, kromer can make that line a good unit, but it's going to take time and teaching/upgrading sub par personnel