The pattern generator is very nice as it is. The only thing I miss is a way to rotate the pattern so it doesn't always start at the first step. Maybe adding a parameter called "rot" which is from 0 to len-1 would be possible?

The first implementation of a euclidean pattern generator I saw was
this for reference.
Comments
;;)
The 8 pattern buttons should probably work the same way they do in performance mode - move to a different pattern... You can move the view with shift+pattern button in patgen mode, but pattern button alone seems to do nothing in patgen mode.