I'm not sure I see that huge of a difference between the old/new EI aspect sculpts. Their differences can be summed up in three points: Different heads (no longer Alien). No more integrated guns. Bulkier upper bodies. The legs are nearly identical. The ratio of armor plating to exposed "muscle mass" is also similar. 1 and 2 certainly contribute to the perception that they are vastly different, as they tend to be focal points of the models themselves, but think about it. The larger the head, the larger the target for a head shot. If you are designing a murder machine, you want to make it's primary sensor area as small a target as possible while still being large enough to house all of the sensors, no? Well, I guess you could justify just about anything through fluff with enough time, so that's kind of moot.
