Concertos are not the place to learn technque. I have a HUGE beef with all of the teachers in the USA who throw the Debussy Danses at a student who can barely play. Aside from simply being able to hit all of the notes, does the student have absolute evenness of tone production in all 8 fingers? Can the student play multiple dynamic levels simultaneously in either hand? Can the student place in sequence, meaning placing only one note at a time ahead of the note being played? Can the student make a quick but even accelerando or ritard, crescendo or dim.? Can the student muffle individual notes with individual fingers in the left hand? Can the student play sixteenth note scales over 4 octaves at 108 to the quarter? That’s a minimum speed. If the student can’t do these things well, then he/she is not ready to learn the Danses, or any other concerto for that matter. I think a good place to start, for the student who is ready(i.e., has the necessary skill level) is the Dittersdorf.