I have thoroughly revised my Passacaglia and this is the result.
Freely following the motto "less is more" I have deleted some passages and adjusted the pedal solo. The full organ above the pedal solo now sounds much better than in the first version (I based it on the similar passage of my toccata "Christ ist erstanden").
I, for one, am very pleased with the result.
At the moment I'm writing a fugue after it (as Geoff and Ralph suggested), but it will take some time before it's ready.
I'm very curious how you like this final version and wish you a nice, sunny Sunday (we're expecting 20 degrees Celsius today in Bonn, Germany).