We welcome you to take part in discussions to <a target="_blank" rel="noopener noreferrer" href="https://github.com/Chocobozzz/PeerTube/issues">help ongoing efforts</a> in that direction or <a target="_blank" rel="noopener noreferrer" href="https://github.com/Chocobozzz/PeerTube/issues/new">suggest new ones</a>!
While viewers themselves contribute a little additional bandwidth while watching the video in their browsers (mostly during surges), mirroring servers have a much greater uplink and will help your instance with sustained higher concurrent streaming.
You're right. PeerTube is not the perfect tool, far from it. And we never promised this software would include all the features corresponding to every use cases.