I went to an isolation float tank once where you get to choose the sounds/music you hear at the beginning and end of the session. I chose “Alpine meadows” that had bees buzzing, light wind moving in trees and grass and little bells chiming and it was my favourite part of the experience, I could have listened to that the whole hour. What you described is very similar and would make a great soundscape for situations like that!
Many have said things that are more immersive sounds or almost soundscapes like rain on roof, but I have a clear favourite short and snappy sound and that is the sound of when a basketball goes clean through the hoop without touching the rim, the so called swish.