This is my go to all through the cold months:

Nashbar Derby Softshell Jacket

As you point out I adjust layers underneath as the weather dictates. These days just a jersey does the job. The only problem is over dressing, you can overheat and sweat up a storm if you overdo it.

I have a red and a hi-vis version. They both have reflective elements. The hi vis is the one I lean towards. Many times have observed it grabbing drivers' attention.