Bissig:
I don't play on FF off servers unless I have no choice (1.2 playtesting servers)
And it depends on area, of course, I'll grant you that. Just don't forget that each of humans needs line of sight too, blocking is also a concern.
But consider this:
Basic dragoon has 200 HP. Shotgun deals 50ish damage with perfect hit, this means at least 4 shots per dragoon. Meanwhile humans often die in 1 hit from a dragoon (I'm not entirely sure if it's pounce+chop which is removed from 1.2, or just pounce). Does higher number of humans versus smaller number of goons really favour humans ? Each time a human dies their collective firepower goes down, and one of them can die really quickly. But it's harder to stop dragoon before it gets to hit something than other way around. For a human, it's often enough to just pop his head around wrong corner to die instantly. Especially in 1.1 where there's no dodge. It's more apparent in S1, without helmets. In many circumstances X goons has advantage over X humans, especially in lower stages.** Effective total power of alien team can be higher than total power of human team. Most s1, s2 humans don't have the skill to solo a goon.
* technically charging tyrant is fast but it can't jump over many things.
**If goons are too fat to put all of them in the same entrance they can attack from two sides, being the fastest creature in the game* it doesn't take long to get to the other base entrance. Ok, goons are not great in tight spots, but this implies they already won a partial victory - they forced humans to concentrate in small area and around tight passages. As soon as humans spread out a bit, they die like flies.
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As for the original post:
in 1.1 stages are based just on kills, and I think this favours aliens ! Vast majority of kills seems to come from dragoons, and dragoons rarely die, and are harder to kill overall. Lack of helmet in S1 is really crippling, no matter what you do you can die in hit hit from dragoon or 2 from dretch.