If this works like the old AirPort Express, shouldn't you be able to turn the WAN port into LAN for a WAN-to-LAN bridge of sort? I used to do that to connect device without Wireless in another floor, it was pretty handy.
That's pretty typical for Apple stuff, though. Although, if I remember right, you can set Apple stuff up as just bridged. I also find it interesting that there's now an iOS app for setting up their APs. That fixes a big gap for some people. I'm just hoping that IPv6 support comes back soon...