+1 on the pit vents. It's amazing how such a small feature makes a huge difference in warmth control and heat dissipation.
I admire you everyday riders. With a gortex shell and long sleeved underarmor tee, I'm good to about 10F. Most all weather is managable but I'll drive when wind gusts over 15, or temps drop below around 10.
I gave up trying to stay dry a long time ago. Now I just use a simple pullover rainjak that's oversized with a hood. Fenders are a must.