When you play these notes: Bes-A-C-B (B-A-C-H in German nomenclature), it's hard to decide what key you are in: in all of them, seemingly all at once. Ha!
So, you feel the piece had to end differently, but I had to stay with the b-a-c-h approach. So, the whole improv was a great exercise in delightful disorientation.
If you feel disoriented as well, well....then I have succeeded. :-)
Hope you enjoy it.
P.S.: turn up your volume for the greatest effect of this fantastic instrument !