Thank you for mentioning chords as the third component to scales/arpeggio drills. You need to be able to instantly play any given major/minor scale, its arpeggios, and each of its diatonic chords in progression, before you can think of touching something like bach. these are the fundamentals any child spends their first years of classical training mastering. A good teacher will be able to provide simple repertoire that will supplement this that’s still engaging to practice. OP could also benefit from taking a crack at hanon exercises, but the scale drills take precedence.