I've noticed a lot of music by New York composers use very interesting and varied, unpredictable accompaniment patterns (syncopation, rests, variation, counter-melodies etc) for their songs (like in Broadway songs and some Jazz etc). This doesn't seem very prevalent in the classical school of thought where often the left hand just matches the rhythm of the right-hand or else, plays a relatively repetitive structure.
Here's a specific example: You'll Be Back (piano accompaniment) This song pretty much inspired my interest in jazzy, broadway-ish music and I think it's my favourite and most interesting to my ears. The sheet music can be found on the internet
Some basic observations I've made about this song: a mixture of straight and swing eighths, and triplets, progression of simple to complex, answer-and-call things/countermelodies, chromatic passing notes but no passing chords per se, highly melodic bassline and sometimes even upper and inner-lines, constantly changing rhythm and inversions with a fair number of gaps/rests with no accompaniment at all, The last section ("da-da-da") had a kind of polyrhythm pattern (straight upbeat groove in right-hand over a swing downbeat groove in the left) which represents a peak in complexity, balance- busy, dense sections are followed up by quieter ones, unpredictability
As for specific questions I have about this song, what is the motivation or theory behind the I, I7 chord progression (G to Gdominant7)? And what is the purpose in using the note D quickly (eighth note) to often transition to the next chord?
I̶ ̶w̶a̶s̶ ̶w̶o̶n̶d̶e̶r̶i̶n̶g̶ ̶i̶f̶ ̶t̶h̶e̶r̶e̶ ̶a̶r̶e̶ ̶a̶n̶y̶ ̶g̶o̶o̶d̶ ̶r̶e̶s̶o̶u̶r̶c̶e̶s̶ ̶o̶r̶ ̶b̶o̶o̶k̶s̶ ̶t̶h̶a̶t̶ ̶t̶e̶a̶c̶h̶ ̶w̶r̶i̶t̶i̶n̶g̶ ̶a̶c̶c̶o̶m̶p̶a̶n̶i̶m̶e̶n̶t̶ ̶p̶a̶t̶t̶e̶r̶n̶s̶/̶r̶h̶y̶t̶h̶m̶s̶ ̶i̶n̶ ̶a̶ ̶m̶o̶r̶e̶ ̶u̶n̶p̶r̶e̶d̶i̶c̶t̶a̶b̶l̶e̶ ̶N̶e̶w̶ ̶Y̶o̶r̶k̶i̶a̶n̶ ̶s̶t̶y̶l̶e̶?̶ ̶T̶h̶e̶ ̶b̶o̶o̶k̶s̶ ̶o̶n̶ ̶a̶c̶c̶o̶m̶p̶a̶n̶i̶m̶e̶n̶t̶ ̶w̶r̶i̶t̶i̶n̶g̶ ̶I̶'̶v̶e̶ ̶m̶a̶n̶a̶g̶e̶d̶ ̶t̶o̶ ̶f̶i̶n̶d̶ ̶a̶r̶e̶ ̶t̶o̶o̶ ̶s̶i̶m̶p̶l̶i̶s̶t̶i̶c̶ ̶a̶n̶d̶ ̶f̶o̶l̶l̶o̶w̶ ̶c̶l̶a̶s̶s̶i̶c̶a̶l̶ ̶t̶h̶i̶n̶k̶i̶n̶g̶.̶
Could I have any general (or specific) advice on how to train/study to be able to write accompaniments like this?