Either way is fine for me. What makes a book enjoyable is quality, not genre, exactly like with people (the word should be gender in this case, but in Italian is the same word so I could not resist adventuring a punch line).
Classic is fine, but probably I have read it if it is good. So the novelty part of the attraction will be partially forfeited.
Something new is always welcome, if it is any good. Preferably shortish. That is a plus for a new thing.