off the top of my head listening I would cut back a bit on the busy piano for starters.
it seems to be saturating the entire song. Or maybe try a nice EP instead.
Is it in the beginning as well as when everyone kicks in? The Arranger playing I left in second half so there are two pianos there.
Also I used a piano with Strings which is probably the saturation. When I tracked originally I NEEDED THE STRINGS because of sparsse arrangement. Maybe I should swap the instrument as you say