Hello to all readers,
I am looking for optimizations of my GL-A1300 router, I am also looking for the UPnP setting if there is such a thing. 
If you really need UPnP you need to install luci-app-upnp
See: Which UPnP for OpenWrt? - Installing and Using OpenWrt - OpenWrt Forum
I would not recommend to use UPnP.