Hey Koen! Great work! I'm no musical expert, but I'd love to give my input on your remix!
First off, I REALLY like your vibe and direction of the piece. I clearly see what you're going for, and the beat and sounds really mesh well together.
The only things that really stuck out to me were:
1. The lower string/synth sound you use in the beginning, starting at around 0:04 sounded really lacking and unrefined. I think since the it's playing by itself mostly, all the concentration is on it, and I think it could sound fuller and a bit more realistic if at all possible.
2. This one is completely just my opinion, but I would love to hear the background parts be much fuller and a more prominent component to the piece. The main melody is great, and I think the background should be supporting the main part more and be less of just background noise.
Again, I'm just a guy that loves music, so take my opinion with a grain of salt. Great work though!