Router is Missing from traceroute Output
When traceroute is run from LAN to a destination on the Internet, the router itself may be missing from the traceroute output depending on the firewall configuration.
This happens on Multi-WAN due to the way that route-to and reply-to work. pf(4) policy routing(route-to/reply-to) does not decrease the IP TTL when forwarding packets, so the router does not appear as a hop.
This may also happen with IPsec due to the way IPsec traffic is handled in the kernel. The traffic is not "routed" in a traditional sense.
This behavior may change in future versions of pfSense, see here: http://redmine.pfsense.org/issues/932