My only knee jerk reaction to your post is that women in aikido are being compared to female gang members.
I have to point out that is not really a fair comparison, and I agree with Lauren that most people, women AND men, who join aikido are not looking to vent aggression.
Now...on to what I think is actually the point...
You know what, I do not think it's necessary to "figure out" the whole "women's issue." I run a women's aikido board and the biggest difference I have seen isn't really that big or huge or very profound. It's just that we like martial arts and aikido in particular and other women don't. I participate on other boards where women dominate - at home fitness and work out enthusiasts. They love to workout, train for marathons and could run circles around a lot of people. A small minority of us on that board actually practice a martial art. Those of us that do practice anywhere from MMA, judo, TKD, aikido, karate or kung fu.
The difference? The great majority of these women are simply not interested in practicing a full-fledged martial art. They'd rather do marathons and triathlons. That's it, really.
The sexism that women do face in aikido really is miniscule. It exists and should be acknowledged when it arises, but please let's keep it in perspective, too.
Now, to your question. You stated that our motivation is different and that our motivation is personal. I can see that in the sense that women, in general (note: not all women), tend to be more social. Therefore, we seek out friendships and sometimes our motivation to go to class might be based upon seeing our other friends. But, this is not always the case. I also disagree in that it's personal, based on my discussions with other women, is that our motivation to train is not all that different from men. We train for spirit forging and for learning self-defense. We think martial arts are cool. Some of want to teach or maybe even start our own dojos. We love the breakfall and to train hard like everyone else.
You see, we really are not that different. And when there are differences it's slight not huge. Differences need to be respected yet kept in perspective.
My suggestion is to just stop trying to figure women out and simply just accept us for who we are and treat us with respect -- which in my experience, the super-great majority of men do anyway. That's it really. No more, no less.