Hi there! If you're looking for something that’s challenging but not too difficult, I’d definitely suggest checking out Note-Store https://note-store.com/ . They have a vast library of intermediate-level piano sheet music that includes a variety of genres, from pop and rock to classical and jazz. It’s a great way to step up your playing without feeling stuck with overly complex pieces. They also organize the music by difficulty, so it’s easy to find exactly what you’re looking for. Whether you prefer PDF files for printing or MIDI files for practicing along with, the site gives you both options. I’ve used it myself and found it to be a fantastic resource for players looking to grow their skills!