Cool stuff. I'm gonna guess you were quoting Three Blind Mice; I haven't seen the show. If not—well, you might have reinvented the wheel.
A couple things:
1. I'm not sure how I like the quiet rolls at the ends of phrases. I know they're possible, but they're gonna be a little awkward and take time, delaying the nice quiet resolution. If I were to suggest a change, I'd maybe consider doing a two note thing (like a grace note + final note kinda thing), with some rolled figure in the keyboard to supplement the effect.
2. I'm guessing you want your many grace notes to connect to the triplet figure that come after them? I'd suggest being really explicit about that if so; string players are literal (e.g., don't bother giving string players phrasing slurs).
3. mm. 23–24 and 72–73: My brain kind of wants to hear some of these plucked for some timbral variety, especially since the keyboard takes over there. Something like the first note is arco, the others are plucked, until the anacrusis to the next bar.
4. I don't think your slow section needs a key signature change, personally, especially because I don't hear your key centers as the implied I–bVI–IV of A-flat major. Think of it like musical theater: you change keys so goddamn much that sometimes it ain't worth it. (Also F-flat major is kinda obnoxious to read).
Nitpicks:
a. Could use some more courtesy accidentals, when used in succession. For instance, throw a courtesy in m. 41 just for funsies.
b. D/C double stop is kinda annoying, and very sad that it moves to Eb/A, which can't use the open A. I see the voice leading, it could maybe be a little more practical, though.
c. Make sure dynamics are on the notes played. I think we really only put dynamics if it's "n" at the end of the note's duration. Maybe it's for the playback.
d. Last measure: take out the rests in the right hand, since it's written like the right hand is doing a register transfer to a lower octave.
Really fun stuff. Congrats.