Isn't it weird how Romanov novelists tend to break down? If they're not writing about Anastasia (big if!), they tend to focus either on Olga --if they're women, or on Tatiana -- if they're men. Somebody could probably write a really dubious dissertation about all this. Olga, sensitive, witty, prone to angry outbursts, not a beauty but attractive nonetheless, appeals to girls and women on an emotional basis, whereas Tatiana, the auburn-haired, almond-eyed beauty, has sex appeal (even though, catty remark, she had an unusually long waist and short legs -- face it, those ample Edwardian skirts really hid a host of faults), hence men's penchant for making her their fictional heroine.
Of course there are exceptions to the rule, Maria has on occasion been a heroine, too, but the overall trend seems obvious to me.