I am about to start a dangerous discussion here: Gender differentiation. For some reason, this seems to be a no-no in roleplaying games. We happily accept humans and Xenos have different builds and have no problem in accepting humans born and raised on starships differ from humans born on hive worlds. But the most obvious difference amongst humans, that the males and the females of the species have a different build, seems to be completely forgotten or probably, avoided.
Now the last I wish to do is to impose 'male chauvinist pig ideas' on role playing. But I like games to attempt to give a realistic portrayal of a non existant reality. This is one of the reasons why I prefer seeing male guardsmen in a fantasy setting, as it is just far more believable from a historic point of view. The second reason is that making male guardsmen the norm, is that it will make female PC guardsmen stand all out the better. How epic would Jeanne d'Arc have been if young girls had regularly lead armies to glory?
As such, I am wondering what good optional rules would be to portray the gender differentiation between male and female humans. Let me clearly say, optional, open to the choice of the player.
Firstly, and most importantly, there is the physical fact that the average female is not as strong as the average male. Females are about 52%-66% as strong as males in the upper body, and 70%-80% as strong in the lower body. This is one of the most important reasons why those male guards mentioned are more believable. If you have to carry armour and wield a club, muscle mass is very important. This is not to say that women can not do it, but males have a definite advantage there. Just as it does not mean that a strong woman will not be able to pound a weak man in the ground, these numbers are all generalisations.
In game terms this might translate in a -5%/-10% strength modifier, and that is quite hefty.
Secondly, males have on average a higher muscle mass, heavier bones and larger hearts pumping more oxygen rich blood around that even clots better then female blood.
So in game terms that might even give toughness modifier, portraying the average stamina difference.
Obviously, this has an impact on the game, as strength and toughness are some of the most important stats, directly impacting the ability of a character to inflict and withstand damage. Just translating the existant physical differences in rules would make female characters far less desirable to play. Which is one of the reasons I would always make any gender differentiation in player characters optional.
But, there might be the option to offset these negative modifiers on basic strength and toughness with positive modifiers on other stats or characteristics.
The problem is, what to choose. Where we can just take a look and confirm the physical difference, I think most people agree that mental and social differences are far harder to measure if they are even there. One thing seems certain, and that is that neither man nor woman is really smarter, more social or more determined.
Still, game balancing would require to enable female characters getting a hefty advantage if they use the optional rule to decrease their strength (and possibly toughness). So I would be all in favour to allow an increase in choice of one of the mental and social characteristics. Of course, this runs the risk of power gaming (female psykers would then outshine male psykers, to mention but one problem). Another option is to grant female characters extra skills to make up the physical stat difference, but on the long term this is not really a fair trade off.
Alternatively, we could make female characters more heroic. Taking on a world were physical violence is a common thing while being less well equipped by mother nature is a brave act of defiance, that shows the true grit of a real hero. This can be translated in luck, the eye of the God-Emperor watching over you and quickly picking up everything around you. An additional fate point would sound quite right and faster skill progressions (say a 10% XP bonus) might not be unlogical either (like the good old D&D XP bonus for wise priests or strong fighters, those characters were obviously born heroes). In each case, this might offset the optional malus.
I know I am hazarding myself on thin ice here, and I hope the female readers will forgive me broaching this subject. But trust me, the last thing I wish to do is to create difficulties for girl gamers. The more, the merrier. It is only my wish to reinforce the suspension of disbelief that makes me consider these rules. And, the wish to make female characters all the more heroic.
Friedrich van Riebeeck, Navigator Primus, Heart of the Void