I wear a base layer under my jersey all year in CA. In the winter it keeps me warm. In the summer it keeps me cool. Cool you say? As it dampens from my sweat with the moving air it works as a cooler for me. (You have to keep riding for this to work.) I always wear my base layer against my body. I really don’t even notice it anymore with or without a bib or shorts. I do have two types of base layers; one is long sleeved and slightly heavier material, but still wicking material while the other is short sleeved and very light material. I have Wal-Mart, Voler and Craft. I got to tell you Craft is the best one. (Craft was a gift from the spousal unit.) Second best are the Voler base layers I bought. It is all about fit and function.
And then again, I also wear a skull cap over a full head of hair all year. If I were to over heat it would be easy to peal off and store these items.
I would buy
Voler again. They run $18-$35 each.