Hi @Small_Garden_Product, in my opinion there are some issues in your track, first the title suggests a piece mainly of piano, but the piano is not for me in the foreground, it starts to play at 0:29 and the melody starting at 0:46 is more in background than the other instruments.
But the main issue is the delay on the glokenspiel and the strings sound, especially when the piano starts to play the melody.
It’s only my opinion anyway, for sure you can improve the track sound, good luck! 
Try to star with piano track and gradually add other instruments during composition.
I also think that delay on glockenspiel is not necessary. Unless if it is a trance track, don’t use delay on plucked sounds
Thanks for your advise. It’s really helpful.
Do you know In what loudness specs do we have to mix.
-10dbfs, 0dbfs or - 24lufs
mmm, I always export with -1 True Peak… 0.3dB is a bit too high, when converting to mp3 or other formats it can lead to clipping.
Spotify even recommends -2 dB for louder songs!
http://productionadvice.co.uk/spotify-upload-true-peak/
Since I follow the -1dB I have less clipping problems when exporting to mp3 or when encoding to video.
Now for LUFS… I wanted NOT to be part of the loudness war, so I decided to go for -12, but in my genre (Hiphop and/or Metal) I was sooooo quieter than the other songs… So I decided to go for -10 LUFS.
I recommend the free, simple dpMeter3 VST to check the LUFS levels.
Hello @Small_Garden_Product and welcome…
well, many things to say… listening to headphones, something is strange with the stereo image, I am not sure what is wrong, but it just feels unatural (phase problem?)
Now, I expected a soft piano track, but the piano is a background element.
The strings and glockenspiel are a bit too loud to my state!
I find the best part of the song is from 1:14, where elements blend a bit better together.
Thanks
Thanks a lot