Setting is cool and the music is great, for just piano sketches they each really set a mood.
Mix wise the piano could use some reverb to help make the sound more stereo/spacious, since as is its pretty mono feeling in the middle and that could help enhance the dreamy vibe that the calmer tracks had. Having the reverb on its own bus that you send the piano signal to, and cutting the low and high end of the signal before the reverb can help cut out the low end mud from the reverb and use more reverb to really get a spacious sound (usually called the abbey road reverb trick if you want to read up on it).
Since the LABS Soft Piano is a felt piano it will naturally be a bit muffled sounding, but for the autograph grand that you probably used in Underneath I don't know why it has that bit muffled character since it's not a felt piano sound, maybe you EQ'd the high end a bit too much? I'm not sure, but a bit more brighter sound would fit the setting described for Underneath more IMO.
A Field of Flowers had a great atmosphere, kinda got the same feelings that some of C418's minecraft stuff gives me with the sort of calm and serene atmosphere of it.
If you ever arrange these you got some great material here! For me the two peaceful tracks felt like that some strings, woodwinds and maybe some tuned percussion/bells would work great for the vibe of them.
Good work!