yeah, 50's is like a warm Seattle winter day (as opposed to a cold Seattle winter day) and that sounds like a lot too much to wear while riding.
When the temp is 40 degrees, I need a light hat, warm gloves (or double gloves)
a light-medium wool inside layer (think of a cashmere sweater) then on top of that, a bike jersey and on top of that a raincoat. add booties and that's really it for that temperate. when it's in the 50's I wear just that inside sweater and a jersey on top and maybe a light vest - while riding.

m