My experiments using the demo song chords yielded the same results as you report. Tried forcing the vocals to a simple arrangement, which did not change my results much, if any.

Y'know, it sounds pretty cool if you don't look at the chords. But choices like singing a G# over an Em just don't fit in any of my musical contexts.

My early attempts to use the Oohs/Aahs were similarly frustrating, but these have gotten better over time with PGMusic's improvements, and are now often very useful. Hopefully these newer ones will improve as well.

Sorry I can't offer much more.

DC Ron
BiaB Audiophile
Presonus Studio One
StudioCat DAW dual screen
Presonus Faderport 16
Too many guitars (is that a thing?)