Briilliant playing! While on the whole the tempi were slightly fast for my taste, that is really a personal issue, and I find the mystery and dream-like qualities were emphasized even in your tempi, which I greatly appreciated.
Especially in the first Impromptu, where the tempo was probably closest to what I imagine to be true; a meditative sense was really captured and maintained in those flowing dialogue passages (where the left hand plays question-and-answer in the treble and bass against right hand's constant figuration).
Those passages bring to mind for me a short story of Hesse, Flötentraum, where the main character is an innocent observer of life, who eventually ends up on a boat with a Cheron-like figure, and asks such ominous questions as, "Can I return to shore?" and Cheron gives him only terrifying silence, or negatives. While the Schubert is perhaps not so pessimistic, the Hesse story also has an element of Romanticism, and they meet somewhere in between.
I found the second Impromptu fast, but then again it is marked Allegretto, and too many people sentimentalize it and play it in sloppy, wishy-washy rhythm, which you decidedly do not do. The trill in the trio section bringing back the major key sent chills up my spine!
The third definitely seems to fast for the character of the music, but thankfully you maintain the dream-like quality. The minor variation seems to me the most faithfully played and closest to what I hear when I read this score; are you perhaps one of those people that excels at minor keys and zips through the major ones?
More on the fourth later.
A Hearty Congratulations!
Walter Ramsey