I think it matters more for women like Veronica, who is so incredibly tiny, or for Russell, who’s unusually tall, b/c it enables a different kind of mobility or different challenges. But fictional detective work usually requires a fair amount of activity, and thus physicality is a necessary element in sleuthing.

Unless you’re Nancy Drew, in which case it only matters that you have Titian hair and always keep your hanky clean.

Elizabeth Peters’s detectives are women, too, and she does bring in their physical bodies–but she in much the same way as does with her male. Even those things that make her female characters seem like a male fantasy are treated as an irritation, rather than something to be proud of. (With Peabody, at least, the physical characteristics are often more of a hinderance. Peabody is…ahem…apparently very well-endowed, and it occasionally stops her from crawling through narrow spaces. Not that her husband Emerson, who’s quite a large man, does much better. But they’re archaeologists, so they’re good at squeezing into tight places.)

Similarly, Peters’s Vicky Bliss finds being an almost-6′ blonde woman with a Barbie-doll figure an incredible irritation. It makes her stand out in a crowd. (It’s interesting that Peters pairs Vicky with a man who probably looks like a handsomer version of Peter Wimsey–relatively slender, average size, probably blonde–whose great skill is that he can be anyone he wants to be. He’s a master of disguise. He is also either exactly Vicky’s height or slightly shorter.)

First of all, King does directly address Holmes’s canonical attitude towards women. Russell writes:
Looking back, I think that the largest barrier to our association with Holmes himself, that inborn part of him that spoke the language of social customs, and particularly that portion of his makeup that saw women as some tribe of foreign and no-entirely-trustworthy exotics. Again, events conspired. Holmes was, after all, unconventional and outright bohemian in his acquaintances and in his business dealings. His friendships ran the social spectrum from the younger son of a duke through the staid and conventional Dr. Watson to a Whitechapel pawnbroker, and his profession brought him into contact with kings, and sewer-men, and ladies of uncertain virtue. …. Perhaps, too, there is some truth in the immutability of first impressions.
Because when Holmes first meets Russell, he honestly thinks she’s a boy. It’s Russell’s first (and only, for a long time) triumph over him–that he is totally mistaken as to her sex. His view of her is heavily informed by that first impression of her as a boy. What’s more, King makes it very, very clear how truly startled Holmes is to find a mind exactly like his own in a 15-year-old girl.

The love story is a true meeting of the minds–it’s the rare chance of finding a true intellectual equal (for two people with that hard, diamond-like brilliance that defines Holmes) that creates the love between them.

As for the age thing, King addresses it somewhere, including a timeline for her justification of the revision of Holmes’s age. That Watson has fictionalized his stories is emphasized throughout Russell’s narrative; I think on her website, maybe, King lays out what informed her decision to make Holmes younger than he is in canon.

As far as Holmes not marrying…because King emphasizes the extent to which the stories are told from Watson’s POV, she also emphasizes how much Watson has missed or left out. Not that he doesn’t understand Holmes, b/c he does, in his way. But King’s Watson sees that hard brilliance and distance from humanity, and not the extent to which even Sherlock Holmes has to have some human nature in his soul. (Otherwise, he’d be a sociopath.) (I admit that King’s Holmes, though, is not Conan Doyle’s, and I’m okay with that. Other Holmeses, who are perhaps closer to Doyle’s, are still infused with humanity and even, occasionally, love. I can’t see how that betrays the spirit of Conan Doyle.)

It also makes no sense for Watson to do such a thing at the very beginning of their acquaintance and living arrangements, not knowing that there would be a future market for his stories of his

If he’s writing the stories, then he’s assuming a market. Why not change some of the facts to make it more acceptable to a broader audience? If he wrote the stories later, then he knows there’s an audience. If he wrote them at the time things were going on, he’s assuming that someone, somewhere, will want to read them, and marketing the stories will necessarily be a part of that. The difference is that Conan Doyle’s Watson is a chronicler–he’s writing strict non-fiction. King’s is a fictional biographer–he’s writing the truth, but telling it slant, demonstrating a certain level of literary and business acumen.

Hey, Dormouse, do you want to weigh in on this, since you’ve read farther in the series?

The age difference between them is supposed to be 39 years. It might not give you the ickies if you read King’s books . . . but this would not be Doyle’s Sherlock Holmes, so it might be too frustrating for you. It seems some Amazon readers feel the same way!