Beautiful composition! It definitely conveys that sense of peacefulness and deep emotion, which is something I don't think is easy to get right.
Tiny nitpick: Do your string and flute VSTs support different articulations (slurring, etc)? If not, I'd recommend finding some from Spitfire - they have a cool function where you can switch between different articulations easily just using out-of-range notes in the MIDI. I think using those might make it sound a bit more natural.