WiFi Routers to Connect Photons and P1s, What Works Best?

I have had some issues with the 2.4 GHz channel on a NIghtHawk X6 router. Over time it stops connecting… I believe its the router because there are networked thermostats in the same environment that occasionally get knocked offline as well. Router logs don’t offer much information.

I think the community would benefit from a discussion on what WiFi equipment/hardware would work the best for the least amount of connection loss.

There is everything from high density Cisco gear to Linux based raspberry Pi devices (Beaglebone, Banana Pro, etc…)

What WiFi router/gateway works best?

What are the important criteria, such as antenna design, router OS, and others?