I have found myself using the drop down menu to make a playlsit track into an instrument track, with the 'use existing channel' more often than any other thing related to the new instrument track feature. On the other hand, I have not once used the list of generator plugins to begin a new instrument track from the playlist.
I thing the 'existing tracks' should be listed in a separate menu item, or relocated. As it stands, I must mouse all the way to the top of the screen in order to find the submenu which lists the existing tracks. I would rather the plugin database be in this submenu.
Another useful option might be to 'use all existing channels' to create instrument tracks, all at once.
Instrument track 'Use existing channel' - re-arrange
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