Greetings, before anything my greatest thanks for your effors developing such a good firmware for our routers, personally i have 6 routers and i use your firmware on each one to make an openvpn connection between or warehouses and offices across the country. In my day to day work i have realized a very good feature that would be handy to have.
in order to restrict outbound traffic i have manually edited the firewall config file to redirect every request to a public IP to our own server, this allow me to create custom error pages (where the user can't browse to some page) or to redirect traffic, in our case we have a qmail server in our main office and with the same subnet as the clients but with different internet links, with this feature it is possible to redirect all the web and mail traffic to the server trougth the internal network instead of the internet, speeding up all the operations we do with the server. an example of the config is as follows:
config redirect 'redirect_enabled_number_0'
option name 'outbound_traffic'
option src 'lan'
option dest 'wan'
option proto 'tcp'
option src_dip 'public ip'
option src_dport '587'
option dest_ip 'internal ip'
option dest_port '587'
Thanks for your attention, greetings.