i swear I saw some Physical differences, mostly on the bottom of the Eng hull
i intend to tweak the Excelc and Ent B for my own purposes, anyway (without releasing, of course). I may add the same kinds of tweak for an 'alternate Mirrorverse' pair I have as well, where the Vulcans ended up making a UFP (or in this case, a UVE) out of the terran empire.