From your post, this appears to be more of a question around study habits rather than technique. Considering your listed repertoire, Ballade 1 is within reach. What you could work on improving is practice efficiency and discipline. For example, if you only have 15 minutes to practice in a given day, don't practice the part that makes you feel good, practice the part that needs the greatest amount of attention.
Never say you are done with a piece: that puts you into a mindset of closing off growth opportunities and inhibiting learning initiatives. What you can do is set goals. Say that you have achieved your goal. For example, the goal of committing an entire piece to memory, the goal of preparing a piece so you can deliver a reasonably coherent performance in private practice, the goal of getting the piece to a point where you can perform it for close friends, the goal of getting the piece to a point where you can use it for an audition, etc. Music is a life long process of learning.