I'll third the desire. We've been turning the WiFi off at night, and virtually every AP we've had has had issues. So I'd much rather use ethernet for something as critical as security, due to past WiFi issues.
I'm getting suspicious of WiFi's actual safety, potential EMF sensitivity and all that. The same wavelength at higher powers cooks food and has never actually been proven safe at lower levels. Even though it's non-ionizing radiation ... so are the various nuclear radiation particles/waves. So we're running a test to see if turning the WiFi off affects our sleep.
I would worry more about your neighbors using your network, the transmitter in your cellphone is much more powerful than in your AP, and I will guess that you sleep much nearer to it as well... In either case, the strength falls off with the square of the distance.