First this, what you are into is called a Rut. You seem to be blocked, and the best thing is to find another teacher, or a friend who has a better level than you do. There are lots of exercices in the trick section of this site, go check some of them.

When you play a note per beat at 240 BPM, You actually play quarter notes at 60 BPM, it's easier to let your hear build itself if you start playing exercices at this kind of tempo.

To let your fingers fly like Kirk's, practice so that you can play what you hear in your head. It'sa long path, but eventually you'll be able to improvise lines. Speed will come in time.