Instead of laying out patterns into sections into song arrangements I have been recording myself raw improved live jamming on tunes and exporting those recordings. I found I was getting blocked in 8 second loops and nothing output for a year or two when trying to make arrangements of songs after years of doing it that way and have been live jamming recording last 4 years with great results.
Why does the bpm drop? You on analog gear working realtime? Nice flow again... but why