My thought was the WiFi icon should turn into a progress indicator to show that its snoozing, maybe like how apps show they are installing by graying it out in a circular sweep.
They actually have a way to show this. If you play around with the other buttons and modes they seem to use colored for on/connected, grey for on/disconnected, and grey with a line through it for radio off.
If you put your iPhone in "Airplane" mode, the wifi shows "OFF" (with a slash through it) vs toggling the wifi button just grays it out and shows "not connected"
Maybe a lighter shade of blue? Or a white background with the icon colored vivid blue?