My favourite jacket for cold, rainy conditions is Paramo. I've been riding all day in the heaviest of rain (so hard it hurt my face) and still feel comfortable.
A merinio wool base is recomended, the NZ ones are very good. You dont need a cycling cut with rear pockets, just a plain T shirt.
Feet are the biggest problem Sealskin socks have worked well for me but recently the failed leaving me reverting to plastic bags.
A neck tube is useful at lover temps.
I only use a head covering at near zero C. The helmet keeps me warm enough. Dont use an expensive heavily vented one.