Hostcaches are not nessary if you make the clients automatically share their node lists with each other in order of rank with speed and relibility in mind.
this would have a spidering effect all the way down to dial up users sharing with each other and downloading from t3 cable dsl etc
keep a list of the fastest nodes and share these nodes first.
no need for host caches because the client just grabs the local ip from the preloaded list of nodes that are static and this is a changable text file witch you can download from any good gnutella site.