I'm glad someone said it!
I wear a polypropylene top layer (rarely do I need the bottoms) and yes I have an old skivvy style thermal top that is BRILLIANT ... but fluro stripes. My current thermals are from Rays Tent City and are olive green and long sleeved ... wish they made a skivvy style though!
My fleece is Stoney Creek I think ... but I'm just as likely to ditch the top (bulky) for a thinner KMart bought drab olive green fleece that cost $8. If its cold though I wear the Stoney Ck as its ability to zip up around your neck is appreciated. Bottom is a thin fleece, it'd have to be well below freezing for me to wear thermal bottoms.
I always have a beanie either on my head or in the pack!
Final shell layer is either GoreTex if in severe conditions, or a cheap nylon rain jacket if in less severe conditions.
Two things worth remembering: 1. LAYERS!!!! 2. Wet and warm is fine, wet and cold are LETHAL.
Thick socks can be a disadvantage depending on your boots. Really thick socks with tight boots laced up will give you cold feet as the compression limits blood flow. A thinner pair will keep your feet warmer if that's the case. If its really cold, a face shield is nice on the lungs especially if you have to do anything really active.
DONT wear anything cotton, I feel the same about wool which when wet is heavy. Modern synthetics are brilliant. I've 'dried' my thermals at -35degC so that they were stiff as a board, cracked them to remove the ice then put them straight on. You'll be feeling warm within 30seconds. Likewise a fleece.
Cheers...
Con