That "etc." hides "moving the heaviest, most flammable and non-extinguishable part of the drivetrain into a primary crumple zone in front of you" pretty neatly. :D
However, lithium fires burn hotter and can't be contained as easily. So, that firewall may need an update, too.
Plus, as I noted in the weight part, an engine in a compartment is designed to detach and slide down to protect the cell. Can every retrofitter guarantee the same thing for their battery packs?