I would be in favor of a closer 6-to-4 gateway. Here in Los Angeles, it seems that the closest gateway by network topography (i.e. fewest hops) is in Amsterdam! Micro$oft suposedly operates one (presumedly in Washington State) and there are others in the U.S., but nothing closer by routing.
The last part of my traceroute to it reveals which gate I'm routed to:
15 ge-0.2.0.core1.ams.bb.your.org (184.108.40.206) 158.056 ms 157.265 ms 156.991 ms
16 220.127.116.11 (18.104.22.168) 157.722 ms 157.730 ms 158.057 ms
16 hops to get there! Ack! BTW, "your.org" is a European tunnel broker (contracted with "sixxs.org").
I don't know which gateways people are using to get to me, but I do see about 2-3 2002::/16 visitors per day in my web server logs. (Many haven't registered their reverse DNS zones at https://6to4.nro.net/