Are there any interesting present-day or historical uses of "resistor priority" logic?
I don't know of any examples that use the "analog" priority scheme you propose, at least beyond two levels, but the CAN bus achieves an even greater number of priority levels through how messages are transmitted. Low bits are transmitted actively, while high bits are transmitted by letting the bus return to its idle state. Each message begins with an identifier number, sent MSB first, and low identifiers have priority.  As a device begins transmitting, it also monitors the bus to see if the bus state matches what it's sending. If the bit on the bus doesn't match what is being sent, then another device must simultaneously be sending a higher priority message, and transmission stops to let the high priority message through.