Really, just my constant struggle to keep a number of "tunes" in memory. Not especially fancy or long pieces. No real technical problems I'm working at, although there are many challenges I encounter in sight-reading that get attention from me as they arise.
Basically just play more, and not go months without playing. Anything, really: Bach sinfonias, things from the WTC, or, ideally, pieces from my soon-to-be-memorized-were-i-not-so-lazy "book" of repertoire.
And replace the damned CR2032 battery in the Hammond-Suzuki digital clone! Now that I finally got it stacked on top of the digital piano and MIDI'd up to the same (for use as a lower manual), there's no reason except sheer laziness to not unscrew the housing and put a new battery in! Not strictly a piano "resolution," but piano-adjacent.