It's all about the layering system as a whole, not just a "base" layer.
You should start with a good wicking layer: silk, poly pro,etc. to help keep the moisture away from the body. (NO COTTON)
Then your insulation layer, which can be a combination of layers: say different weight insulatied underwear(pending the temps of the day), fleece, wool, etc. (NO COTTON)
Then your weather/shielding layer: for this you want windproof, waterproof/repellent. (can be insulated or non, your choice)
The trick is to have all of the above available and to mix and match the layers according to your needs and the weather conditions/temps.
I live and hunt in a much colder region of the country than you do, so I have grown up working this system out.
(TOP)I personally use a good quality poly pro base shirt(long sleeve) then I have 3 different weights of insulated underwear I choose from, according to the temp. and situation I will be hunting(sitting, walking, or combo of both)I combine the underwear with one of two polartec pull overs, (a regular one, and one with windshear liner) I use a blaze orange cover shirt(chamios)over the top for visibility.
(BOTTOM) I wear one layer of underwear(weigh pending conditions), will add a pair of polar fleece legging(sweats cut off at the knees) if needed, covered with camo BDU pants. If it rains or gets windy. I have a pair of windproof/waterproof over pants I carry in my pack.
(FEET) poly pro sock liners, wool socks and Mucks
I carry my insulated parka with me rolled up on my pack as well, if needed.
FDXX75