I'm not good at Solitaire, and, well, I can say I'm terrible at this game! x)
The concept is interesting though. It has great educative potential. However, despite understanding the music theory concepts used in this game, I've been unable to find the right strategy (as I said, not good at Solitaire :p). Most of the time I see two cards that could potentially do a triad, but then I don't find a third one, so I pick one more or less randomly hoping to find an opportunity next time, then repeat... I'm sure there's a more "clever" way to play, but I couldn't find the way of solving the puzzles the game offers. x) Maybe some kind of tutorial could hint on the methodology the player should learn? It could also make the game more accessible for players who don't know what a triad is.
Alternatively, I could also spend more time on it. Because I still feel that the use of chords here is a clever mechanic, and I want to get better at it. The game is all about finding patterns, maybe time would allow me to see them more easily as I practice it? Anyway, great idea here!