As it stands, at least on Veteran difficulty, civilians are 95% free points for the aliens since it's impossible to save them unless you're willing to take massive losses among your own men. And sometimes not even that is enough to save an acceptable number. I understand civvies work no different than in the original game, but the alien AI has been substantially improved since then, and I think the former require some attention as well.
There's not really much unarmed humans can do against alien soldiers, but they should at least show some instinct of self-preservation instead of wandering around aimlessly, oblivious to the extraterrestrial attack and waiting to get facial plasma surgery.
I don't suggest changing the way they spawn, but wherever they appear, they should...
1) rush (or stay) indoors and find some place to hide, among furniture and/or away from windows.
2) run away from any alien they spot, or at least try to break line of sight.