Mechanically they wouldn’t add a lot, but contextually I feel they’d be great.
Throwing few wives/daughters/maids/whores into the mix of civilian battle encounters would be cool.
And they could feature in rescue/defend quests (men too). And more offensively in unregulated armies, infrequently in mobs and commonly in zombie-hordes.
With female recruitment; I’m sure there are many reasons a woman might flee their oppressive or mundane life (i.e. a witch hunt), and their stories would be interesting to read and could create interesting events around their backgrounds and how men might react to a woman in the ranks.
But that’s a lot of artwork to do female bodies/heads, hair, clothing, icons, etc.