I would have taken the bait, Shad0w, but I've actually changed my position on this issue.
After further discussions on passive media sexism, I've had an epiphany, a Road to Damascus conversion.
Two factors (among others) were instrumental in changing my mind.
(1) Mass Perception vs. Enlightened Perception
I may be modernist enough to see self-parodying humour in Barbarella-style media, which Mage Wars definitely models itself on, whilst still retaining my respect for women, a belief that beauty pageants are crassly offensive and promote self-hate, eating disorders etc, even appreciation that women are often disenfranchised in society so, at the risk of condescending, need more encouragement (confidence is a more male trait and self-criticism more female).
But just because I can distinguish real life issues and fantasy pastiche does not mean others can. Sophisticates may say "oh, it's sooo avant garde!" about Madonna's Sex coffee table book but to many, it's just exploitative softcore porn (I veered towards porn as only a few images were striking, even thought-provoking, hence art). In the same way, I can see the gloriously over-the-top parody in Sin City (e.g. "just give it to him good" said facing camera) but to many others, it's an ultra-violent tale gratuitously filled with scantily dressed women that hides its violence, especially towards women, under a veneer of surreal imagery. So who is to say such media images would not propagate violence towards women in the mind of someone less able to perceive the artistic style and tone?
So just because liberal intelligentsia see no harm in an image does not mean it is not harmful. You have to view it from the point of view of the more prevalant consumer. In the case of Mage Wars, it is the geek demographic who, if I am to propagate stereotypes, are blessed with mental intelligence but often lack "social intelligence". This all harks back to Kich's "We're too smart to be sexist" comment on page 1 of this thread. I think there's a danger that we mix mental intelligence with social intelligence and this confidence will unwittingly lure us into supporting views that, if seen through the eyes of "Joe or Jane Doe", the average person on the street, would be seen as inadvertently endorsing a sexist viewpoint.
(2) Imprinting Children - Generational Cultural Change
The other issue is linked to my "change is incremental" belief and is the effect images have on the young. Many Mage Wars afficionados will teach their children the game. Just as every generation is less racist than the last (my grandmother), it is important to promote more positive images of women seen in traditional male roles (and vice versa) so as to not close doors or gender stereotype.
This is the Nature vs. Nurture chestnut. Children are not born racist or sexist. It's imprinted on them from an early age by the environment, the parents who pass on their own value systems to them, be it a pink or a blue room or a Cooking Set vs. a Chemistry Set. It's therefore important to be enlightened around children so that, if this is propagated through the generations, the environment slowly changes to be less sexist over time until a tipping point when this becomes prevalent. Change is incremental - there are very few cultural forest fires.
As a non-parent, I have to be more aware of the concerns of parents, their worries of how imagery develop children during their formative years. This is very relevant to Mage Wars where there would be inter-generational pressure to play with the parent's latest obsession, and where a child, eager to please, may copy inadvertent sexism inherent in the activity by taking it at face value, lacking an adult sophisticated mindset. Parents can really mess up children without knowing it (I speak from experience).
Summary
And so, at the risk of being labelled a "Kharhaz" (that species renown for jumping over fences and switching camps at the drop of a hat, albeit on facile game mechanic issues), I have now been convinced (by friends and Trotsy's post above which resonated with me) that it would be best to err on the side of prudery and be labelled a killjoy, at least for my conscience so that I am not inadvertently indoctrinating children or propagating mainstream prejudices.
It would be great if the whole world could distinguish between fantasy and reality easily.
It would be great if children were not vulnerable to imprinting.
But sadly, this is not the case and I now feel ashamed I was provoked (after my initial fence-sitting) into playing to the gallery.
Geeks have a proud tradition of being ahead of society's cultural mores.
The first TV inter-racial kiss.
Gay and lesbian major characters.
Equal gender opportunity utopias.
We should be proud we're often more enlightened than the mainstream.
So it's a shame than we're not vocal in criticising a mainstream agenda.
Instead, we opt for the elitist non-confrontational cop-out that is...
"We geeks are far too smart or sophisticated to ever be sexist".
Addendum to ensure topic relevance:
What can Arcane Wonders do about this issue?
It would be asking much to suggest a jarring change of art style that risks alienating their core base.
They are primarily a business, not political, thus will succumb to business incentives and pressures.
After all, commissioning art pieces is expensive.
The suggestion of a Booster Pack of alternative art for old cards (sold at small profit) is a great idea.
After all, if this helps current evangelists convert non-players who otherwise find it offensive, great!
Going forward, I would suggest a move from Solus to Portfolio Marketing.
Instead of just 1 expansion, have 2 - identical except for ALL the artwork.
The Classic edition will have artwork in its Retro style for its current fans.
The Modern edition will have artwork in a Modernist style so not offensive.
The OCD collectors may even buy both sets just for the different art styles.
Then they track sales of these 2 editions before deciding their next action.
Create a "Diet Coke variant "of Mage Wars then let Supply & Demand rule.
Leverage the marketing adage: "threats are just opportunities in disguise".
Let's not ask for too much, for then you just get none!
After all, in life, the reality is: "change is incremental".