Regarding "shooting" yourself:
I don't think a soldier would be able to kill himself directly unless his morale was through the floor. To help compensate for that, though, it would be better if a soldier's morale dynamically changed with each step, based on the number and power of the enemies he could see: so if your aforementioned soldier waltzed into a room of chrysalids, and they turned to him, he could give them the finger, suck on the barrel of his pistol, and paint the doorjamb with grey matter.
(Digression: Of course, that begs the question why a chrysalid spore couldn't successfully incubate in dead, still-warm tissue, unless it's a parasitic entity that latches onto the medulla oblongata in order to brainsuck neurotransmitters as one of its nutrient sources (etc., etc.).)
A soldier who catches himself flat-footed when he walks into a room with a lone chrysalid will probably still think he has a fighting chance against that sucker, and would be much too surprised to be able to do anything to himself anyway. In most cases, soldiers wait until they're mentally ready (full TUs -- i.e., start of next turn) before breaching a room.
Regarding "stunning" yourself, instead:
I think stunning a soldier to protect him was an exploit/bug, not an intentional feature. This is only made more evident by how civilians react to such "protection". Thus, a soldier zapping himself with a stun weapon would make himself a perfect feeding target for any alien creature. ;-)
It would also be neat if aliens like sectoids and other creatures would pick up stunned and dead X-COM agents and bring them back to their UFOs, presumably in order to extract DNA (sectoids), extract gametes (Next week on Jerry Springer: "My husband is an alien!"), or extract protein ("Meat group!").
Edited by jtgibson, 24 August 2005 - 05:35 PM.