One of the many Bach children, Carl Philip Emmanuel, was perhaps the greatest composer (worthy of comparison with JSB, and honored by Mozart among others). He is best known for keyboard music full of imaginative color and flights of fancy.
Here is one of hundreds of his keyboard pieces, the evocative farewell to his Silbermann Clavichord. (Here in a piano performance.)
Evocative–and to my ears–some elements of a modern improvisatory feel.
He also wrote lots of ornate showpieces, for the piano, then a relatively new instrument, such as the piano lesson favorite Solfeggietto in C Minor (sorry about the weird open).