@briansaddlebackI've found the key with Debussy.. you need lots of slow practice. The slow practice helps you with clearing all the difficult fingerwork, then you can focus on the tempo after that. Hah, try working any of his Images pieces.. totally another level of difficulty ! Thought I was okay with Reflets dans l'eau until recently preparing for a recital.. boy that's a lot of work involved. Managed to get there in the end. Patience, and slow practice, as usual.
the doctor ad gradus is HARD !!!! much harder than arabesque 1 you could play clair de lune, or the prelude for the pour le piano, pour le piano is very difficult, but you could try
Play his Ballade!
I'd do the entire Children's Corner suite if it were up to me
P.S. The Arabesque is fun to play, though less Debussy-esque (less dissonance). I love that piece.
Which one?
The 1st; I haven't played the 2nd. (Is the 2nd one fun / worth taking the time to learn?)