I have been very interested in the number of kids who have read the Sherlock Holmes books after reading the Mary Russell books. That's great. That's more or less how I rediscovered the Holmes books.
In silent films, quite complex plots are built around action, setting, and the actors' gestures and facial expressions, with a very few storyboards to nail down specific plot points.
The period after the First World War was an extremely different time, so that Sherlock Holmes would have been a different person following 1918 than he was during the Victorian era.