When adding ports, a wise choice is often to add a switch - a nice netgear gigabit switch is usually a good choice with as many ports as you think you could ever need, plus a few... then plug critical but low-speed stuff (like security/automation) into the router directly, then run a cable from the router to the switch and run all your computers, wireless, etc - off that switch; it'll make communications faster between them.
Great advice! Do you have any favorite models for this application?