Here's thought, I just had, while preparing my squad to enter alien craft.
People were prepared for anything and ready to rush into extraterrestrial territory.
And here's thought - If I were in their place, I would be hell of scared and ready to leave something bad in pants. Admit it, those creatures should scare even hardened soldier, should they met one to one. And now, just when my squad member opens (yeah, opens... still quite funny, that humans can easily "open" alien craft doors...) huge door, and my soldiers see something familiar, yet, totally not build by human. It's scary. It's always scary. Some members saw something like that, and they aren't so shocked, thought, it doesn't change fact, that guy could nervous a bit.
So, this whole story is to show you idea in example. Xenonauts have morale, and as I understand, many calculations depends on level of morale. So, basically, in situations, where soldiers are placed in front of unknown conditions (like, what's behind that wall or door? Should I be scared, or not?). In game play, mechanism could be pretty "simple".
If behind door no-one sees tiles (I mean, exactly sees, not uncovers.), than right after soldier opens door, he suffers little morale drop (you know, stress, fear, and so on. All those emotions.)
I'm quite pleased with current morale system, and this tread is just small addition I imagined. May be it's not worth it, may be it could be just a little mod or something, or it's already there and I just totally missed that. Anyway, awesome work, xeno-guys. )