@SDTGisAnEvilWolefGenius
I agree that they're not male dominated. Typically there's a balance between boys/girls. But I think a modern child looking for a female lead might be disappointed.
Peter (Petronella), Penny, Jenny, Harriet and Mary (and even Rose who isn't one of the Lone Piners is still very strong as a character) are all strong (and very different) characters, but you do tend to have David taking the lead, sometimes with Peter, but also as often with Jon-although perhaps that is when Peter is absent. That might be partially as the Mortons are the only ones that are in every book though.
For Malcolm Saville, both the Jilly Series (Mandy) and the Buckingham Series (Juliet) have females that take the leads with more passive boys, but they're harder to get, hence more expensive. "Jane's Country Year" is one that is a one off and there the lead is female, but I think you'll pay through the nose for it, whereas the Lone Pine Series you can normally get for not too ridiculous prices even for some of them in hard back.
I would feel similar about the Swallows and Amazons in that when the Swallows are there then John tends to take the lead naturally a lot of the time, although (especially) Nancy and Titty are strong characters. But in "Picts and the Martyrs" the Swallows aren't there and it is very much girl dominated with only Dick there to represent the boys, and also The Big Six, which is Dot's story.
If Op is looking for books with girls taking a similar role, then ones like Cue for Treason are also good, although you don't know kit is a girl until part way through the story.