During the past few weeks we had to use wing anti-ice almost daily, flying around in that ridiculous winter here in western Europe. Wing anti-ice normally is not required at higher altitudes and at high speed, but during vectoring at reduced speed (around 220 KIAS) and at lower altitudes with temperatures around -5°C to -10°C ice can build up quite quickly.
I would strongly recommend to use wing anti-ice as recommended by the manufacturer (in my case Boeing) and to get rid of that fine white line on the LED whenever it forms, since even a small amount of ice there can have a significant effect on the airflow around the leading edge, especially at high AOA during final approach.
A good indicator for the need to use wing anti-ice can be ice accretion on the windshield wipers or in the corners of the cockpit front windows.
I still don't feel comfortable with the tail not being equipped with ice protection. The horizontal tailplane has a sharper leading edge than the wing and should thus be more susceptible for ice accretion, shouldn't it?
So if the wing picks up ice, chances are that the tail has picked up even more. With a forward C.G. and ice on the horizontal tail, why should that tail not stall during flap extension under extreme conditions? Has there actually ever been an accident caused by a tailplane stall on a jet?