As to the slicing and dicing of stormtroopers into small pieces, JK will use a nifty piece of coding called GHOUL2. Basically it seperates the body into many different areas (arms, legs, torso, head, etc) each of which can be lopped off on its own (well, probably not the head for this game). It also allows you to easily add in "extras" like sunglasses, backpacks, utility belts, etc by "bolting" them onto the player model. It sounds like a very cool system from what I have heard.
I can't say anything definitve about the others except to agree with you about eliminating fall/low cieling damage after a force jump (unless its a really big jump).