### Description

Feature request/suggestion: Currently, the predicative hashing algorithm for dispatcher gives equal weight to all members of the set. It would be convenient to use the rweight attribute to allow something like [weighted rendezvous hashing](https://en.wikipedia.org/wiki/Rendezvous_hashing#Weighted_rendezvous_hash) to provide weighted load balancing will still keeping correct routing for stateless messages (most specifically CANCELs).