I think it's more important to look at Ken Russell's work as a whole rather than put each
film into a either/or catagory.
While the majority of the films (excluding Isadora, Crimes of Passion, The Rainbow, and Whore) have a male protagonist, the relationships between men and women in Russell's films are certainly not one-dimensional.
The men in Russell's films (usually artists of some kind) are often self-obsessed, phsycially or mentally emasculated, driven by relentless energy, or just terminally melancholy. The men and women who surround them must often suffer as a result of their obsessions (such as Nina in the Music Lovers, Elizabeth Siddal in Dante's Inferno (even in death!), or Eric Fenby in Song of Summer).
But in my opinion the most interesting and complex female characters in all of Russell's work are Gudrun and Ursula in Women in Love, and Sophie Brzeska in Savage Messiah. They don't fall into any easy catagory (victim, idealized beauty, femme fatale, etc.) They engage with their male counterparts on a direct and equal footing (although this invariably leads to the destruction of the relationships).
As far as 'Mahler' is concerned, the ending is problematic. But it's important to remember that Alma Mahler (besides marrying a few other writers and artists, most notably Walter Gropius), was responsible for changing much of her written correpsondence including Mahler's own letters which often omitted acquaintances, augmented her own involvement in the writing of Mahler's works, and changed any event that would cast her in a negative light.
I don't know if these revisions had been discovered when Russell made the film. But I don't think it would have changed his depiction of her. After all, I don't think a dream sequence where Alma dances on Mahler's coffin or performs a strip tease on a grammaphone in front his portrait would be considered exactly complementary!