I commend the use of actual research in this, too many ‘redesigns’ tend to forget this and jump straight into Sketch.
However I would say that as an individual it is much easier to do than at a real company, when you have multiple stakeholders, and different opinions on direction, not to mention limited research, UX and development resources. Most of the issues raised in here will be known, and it’s rather a matter of getting the capacity & sign-off to resolve them.
My final comment would be that I would be surprised if this had not been seen by people at SoundCloud, for good or for bad. Things like this can stir up contention, you have to remember that designers at SoundCloud are people too, a factor which I feel people sometimes forget.