Re: Use the Raspberry Pi-Hole
This - totally.
I've had one on my network for a little while. It took some playing about, because my BT Broadband router doesn't allow you to set DNS servers (pi-hole becomes the one you use). I got around it by making the Pi-hole my DHCP server too, but in the latest version they've included the setup of that in the web interface, so even my slight reservations about recommending it are now moot.
On a Pi 2 Model B, it seems to take less than 5% of the CPU to handle a household of 8 devices, but the loading of logs isn't quick.