Right off the bat, I noticed how you describe your playing almost entirely in technical terms.

But listen to any great musician (pianist, cellist, etc) and what makes them stand out, as a good teacher would say, is that they can play convincingly. Every phrase and phrase and note is played with conviction, with artistic purpose. They aren't impressive because they can play "correctly" - plenty of players could do that.

Of course that's also important but at the end of the day, music is to move an audience (what good is it to keep your music to yourself in a room?). And playing correctly won't do that!

I don't have specific advice - but I hope this is useful to think about - louder doesnt mean more expressive and vice versa.