Fabric will be from Mill Direct Textiles, which buys up overstocks (and regular stock) from Polartec (ex. Malden Mills).
The fabrics I'm looking at are all about 11-12 ounces/yard2 (per phone call with Chris at Mill Direct).
-Polartec Powerdry midweight poly/wool blend (inner poly, outer 1/2 & 1/2.) (very stretchy- 100%) $6/yd
-Polartec Power Stretch Poly (very stretchy- 100%) $8/yd
-Polartec Power Stretch nylon/poly (Stretchy- 60% with more durable outer) $8/yd
I think I'll go with the Powerdry wool blend and make these fitted as a base or base+ layer.
A couple other fabrics that look good:
-Polartec Powerdry X-static $6 (low x-static content, thin, 6 ounce weight) May be good for true base layer or summer base layer. I have a couple shirts that are probably this same fabric and the X-static content helps with odor but isn't enough to make them stink-free.
-Polartec Wind Pro Hardface $15 about 12 ounce weight(Almost as stretchy as Power Stretch per Sandy at Mill Direct. Also has hard outer and DWR) This fabric looks like it would make a very good garment, but might be hard to cool off. It's also twice the price which removes it from consideration for my first garment project.
By the way, per Chris, Mill Direct's swatch pack includes all their fabrics from that category. The website doesn't make it clear that it has every color, every fabric. The "Specials" swatch pack currently has over 100 swatches.