1, I definitely agree with others that you can see touches of Hitchcock in this opening sequence. The first thing that stuck out for me is the focus on the blonde. Though I know he didn't always have a blonde as the main feature in his movies, when he did, they tended to be at the forefront. I also noticed he makes you 'focus' on a specific thing, like the staircase, and it made sense, having listened to the video interview. He'd stated he builds sets according to how he'd film the shot.
2. There are definitely themes that we'll see again throughout his career. The blonde at the forefront, the binoculars, the focal points (observing the observer), the use of light and dark, including that ominous shadow of Mr. Levet in the alley surprising Patsy (which made me think of Hitchcock's tv show opening), and finally the way he relies on the actors to be expressive with the eyes (the ghost's eyes and Mrs. Danvers' a la 'Rebecca')
3. I have enjoyed a silent film or two, so I personally didn't think there were limitations. I think the way this was laid out made it clear what was meant to be viewed.