Investigate and graph the representation space
Similar to Word2Vec
etc., it would be interesting (and great for debugging/system characterization) to be able to extract the vector representations of our chroma sequences (i.e. the input "words") and graph them on a 2d axis via PCA or somesuch. (This would require us to also parse the input vectors into chords, e.g. Cmaj, for labeling). Hopefully we'll see clusters of functional relationships between chords, e.g. for the Bach chorales with only C-based keys, which make some musical sense.