I'm not new in atonality but I never have written anything for orchestra in this style. Just to learn, I'm trying to orchestrate Schönberg's six Little Piano Pieces. They're short and good to try.
This is nº 2 (although I've always thought it is in a sort of "extended" G major).
What do you think? The piece is mostly "quiet" and it is not easy to give voice to the whole orchestra in less than a minute.