Nice work!
A peaceful and relaxing track. If I had to give any criticisms, it would be very similar to Snowly's.
The song gives me strong pastoral vibes rather than an urban/metropolitan vibe, although, as you stated, you're using the word interchangeably.
Also, I struggle to imagine this as an underwater theme. I can, but my mind keeps defaulting to, like, a beautiful, sunny village on a plain.
At any rate, you did well on the track~