Let me tell you my point of view. Your proposals seems to me too complicated to implement in the Gnutella network and brings little improvement (IMHO).

I think the worst thing about the network is the traffic needed to stay connected (pings/pongs), and the traffic that all queries generate; this is where all efforts should be made. A modem user will use most of his/her bandwitdh just to stay connected, leaving almost no bandwith for downloads/uploads. A new connection schema may be required to fix this, but then it is difficult to keep compatibility with existing clients. With lower requirements in bandwith for connection you can download/upload faster, and only then you can start to think about swarming d/l or anything else.