Have the same issue with my new Sky Q Hub which only has 2 ethernet ports! Madness. I have sky+hd box, av receiver, NAS and powerline adapter all to plug in.
If I have one cable from the router to the switch, can I still use the other ports on the router? Will they all get equal 'priority', or if I have 4 cables coming from the switch, will they only get 50% of bandwidth if I have one other cable plugged directly into the router?