I find it helps to listen to more accomplished players perform the music. I hears things like dynamics that can be improved that I might not otherwise notice. It gives me a goal of what sound I want to achieve.
I found learning a different genera of music helps to expand on learned skills. I’m classically trained and started to play rockabilly with my guitarist boyfriend. Playing simplified familiar music with 4/4 timing led to trying to improvise and play with another musician. Improv is totally different from reading music notes and playing in an orchestra and it made me grow musically. I feel like a new student with a fantastic ear. Its fun again!