Maybe geo-location would not be so great because two networks in the same physical area might have relatively poor connectivity to each other.
Aggregated IP block might be the ticket. CIDR-Report has both actual and suggested netblock aggregations.
http://www.cidr-report.org/as2.0/#Gains
Shows 562259 reduced to 253420 advertisements. Perhaps too fine-grained, but 250k is not so much bigger than the 45k ASN count.
Idea is to anchor metrics to maximum size BGP routable blocks, which ought to correlate performance-wise down to all the IPs in each block.
BWauths are continuously pairing relays for measurements, and perhaps metrics from that could be mapped to autonomous system numbers
. . .scratch AS, geo-location is better and MaxMind specializes in that
Pinging a FiOS relay in LA takes 75ms while a close-by relay takes 8ms. Both are in AS 701.
tor-relays@lists.torproject.org