You said that you've burned yourself out playing the works of Mozart, Beethoven and Haydn (thankfully you haven't had to venture into the realms of the second Viennese school), so why not take a break from them and play songs you enjoy outside of the classical realm?
Come summer time I tend to focus on pop songs, musicals, and movie soundtracks (Disney!); it's music that is shoved aside by piano teachers for many reasons (with exceptions to some teachers who teach pop primarily), which is unfortunate because most of us grew up and are familiar with these tunes. The same sense of accomplishment can be achieved by learning to play "Hakuna Matata" just as much as it can be achieved learning to play Beethoven's Sonata in G major op.49 no.2, maybe even more from the former if it holds a special place in the performer's heart.
I believe there is too much of a "must" mentality with music teachers, and students, today: you MUST play Bach in order to learn proper finger dexterity; you MUST play classical music in order to be a good piano player; I MUST learn etude op. 10 no.2 otherwise my teacher will be upset; I MUST practice 6 hours a day if I want to be good, and so on. While there is a grain of truth in each statement mentioned, there is also an immense amount of pressure accompanied with it. Yes, classical music is a dying art and there is a pressure mounted on top of every classical teacher who is attempting to keep the art alive, but when that pressure is transferred to the student I believe it only takes away the value of learning classical music.
Anyways, I'll stop my two-cents here. In a nutshell, play some other music genres that you also enjoy (assuming you enjoyed playing Haydn...) : jazz, pop, movie soundtracks, etc. Breakaway from the classical realm for a while to refresh your brain.
Topic: Summer Pieces