This is why I like to argue.....
Example: If you were to play an A minor arpeggiated lick over a C major chord, it's going to sound contrasting. A more consonant sound would be to use a C major arpeggiated lick instead.
To me, this represents misinformation. Amin arps. over a C maj. chord would not sound contrasting. It would sound great..... just like a C6 arp.
Amin(7) = ACE(G)
C6= CEGA
Not contrasting.... the SAME!
Contrasting would be a Db arp. over a C or Amin chord.