Originally Posted by comprex
Under Armour Cold is a good base layer, stay with that.
(Summertime Under Armour is designed to wick and cool, don't use that. It is not as bad as Coolmax, mind, which really feels like an icebox in winter.).
I would look to improve the fleece layer, and possibly the outer shell.
200 weight Polartec or equivalent has been the standard here for a number of years. I suspect that your current fleece is some version of this. With pilling, stretching, chafing I suspect that the original warmth has diminished some.
As I see it, there are several ways to improve the warmth of this layer:
1) Merino wool, brands such as Smartwool, Icebreaker are the non-itch flagships. Pretty much everyone makes wool layers these days though, from Patagonia and Nike to discount labels. You may be able to get reasonable stuff from Target or Malwart that actually improves upon your current fleece.
Optimises: all day and jacketless comfort, possibly cost.
2) Synthetic fleece in a waffle-print pattern. Patagonia call this 'Regulator' technology, but it is available from other brands. It traps much more air than 200-weight first-generation fleece and exchanges air from warm to cool parts of your body because it provides for cross-body airflow.
R2 (Patagoniaspeak) is the typical layering thickness although cold VT days might call for expedition-weight R3. R1 is for spring skiing or 2-layer fall rain hike layering (R1 next to skin and rain shell on top)
Optimises: Breathability for high-perspirers, breathable shells work better with this type of design
3) Polartec PowerStretch or other stretch fleece. This is available in 200 weights, it improves upon your usual fleece because it is tailored to be more fitted to the body, eliminating air gaps. Imho it can work -too- well for spring skiing.
Optimises: Freedom of motion, and helps eliminate layer bunching particularly around the waist and armpits
4) Down vest. My favourite of these is the Western Mountaineering Flash. Alternatively, a zip-in-down layer for your jacket. Nothing else is this warm. I've skied MSA at night, it dropped below -30, and I had no trouble.
Optimises: pure glorious warmth
5) Wind-blocker fleeces. A lot of these fleeces (Windbloc, Windpro, Nailhead) are actually too heavy-duty except for vests.
Some feel like corduroy or velour-surface material. They work, particularly with lighter, airier shells.
Optimises: wind blocking at the front, durability, may be worn as outer layer for spring skiing.
All of the above is to my best knowledge, if someone knows better feel free to point it out.
HH hardshells from around Y2K actually breathe very, very well. If the shell is in reasonable shape and still repels rain I'd consider hanging onto it, for spring skiing if nothing else.
There are many options beyond that, including ones with zip-in down layers (see above). I'll let others monopolise bandwidth for a bit.