I got fed up with Wifi because my neighbours' kit seems to cause so much interference, so I ended up cabling almost everything. I have a couple of cheap TP-Link TL-SG108 gigabit switches in the same location as my modem and router, and cables from there to key locations in the house. Simple (if you're able to physically route the cables), cheap (the switches are around 20 quid a go) and does the job well. At one point I had another TL-SG108 in the box under the TV, but that went after I simplified the TV setup.