After trying various tweaks to improve our home wireless network performance, I did some online research and decided to replace my organic patchwork of access points and extenders with a Netgear Nighthawk R7000 wireless router. I have AT&T DSL so needed to use the provided 2Wire modem, but turned off the wifi on it. The Netgear genie setup program let me use the same SSID and password that the 2Wire was using so I didn't need to reconfigure any of my devices.
The Nighthawk created two networks, one at 2.4 Ghz and the other at 5 Ghz. Performance was immediately improved on both levels of my house and in all corners. We can now stream 3 videos at a time without a hiccup on an 18 Mbps down (advertised) circuit. It was worth every penny.