Well, gives you some experience making them, right? So time has not totally gone to waste.
They all seem to fall over and die at the same time. Was that intentional due to unit or Civ consntraints? Or is it that making them die non-simultaneously would be a royal pain (what I think it would be, though not saying a skilled creator such as yourself couldn't do it)?
Dying simultaneously is much easier to do than non-simultaneously. You have to find something for the other units to do while they are not dying, and that would mean altering the original flc file for the death, or at least altering the unit itself, and then it would be fairly unnatural if they were attacking before dying, because if you disband them... (much problems trying to sync up the deaths so they die in different orders, unless if they were specifically tailored to do so to begin with.)
Because dying all togeather looks unnatural, most other M-units tend to have some of the figures die, and others run away. I actually had some fun altering the explorer M-unit I made (in Playground Mod 2.0), and made some of them spin around while dying, as if it were struck by a blow that sent him spinning, and others run in different directions, etc.
Making M-units is sort of an under-appreciated art IMO, for it takes a bit of time syncing up the attacks, making realistic looking deaths, run animations not robotic, some amusing fidget/victory animation, and some general timing issues for most all of the animations. This only looks nice if it's for organic units, for a bunch of tanks or ships together look cluttered IMO. Also, since most people don't have a special need for M-units, people tend to make few M-units.