Mine go by the status of the soul, on extreme emotions, and even the original vb is a compound.
Normal vb > Violet Aura or Aura (think of chakra)
Falsetto append > Delirium Aura or DELIRIVM
Power append > Glorious Aura or Gloria (=Gloriosa)
Whispery/Soft append > R.E.M. Aura or REM
Dark append...