I’d have to see it from other angles, but the redesign on the main body seems to have removed any ‘personality’ that the original design had. It didn’t have a ‘mouth’ so much as an inlaid radiator that gave the impression of a frowning maw. The old design had a lot of thought put into it, not only mechanically but as a character. ED-209 was supposed to be dangerous but over designed and comically flawed, hence the stair scene. This one just looks like someone drew a kill-bot over the old silhouette without giving much thought to it’s use in the film, which hopefully says more about how little ED-209 is involved in this new film as anything like a character, and less about how rushed and ill conceived this retelling may be.